Patent Publication Number: US-2022211374-A1

Title: Handheld electromechanical surgical system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation Application of U.S. patent application Ser. No. 16/586,244, filed on Sep. 27, 2019, which is a Continuation application of U.S. patent application Ser. No. 15/612,542 (now U.S. Pat. No. 10,426,466), filed on Jun. 2, 2017, which is a Continuation-in-part application of U.S. patent application Ser. No. 15/096,399 (now U.S. Pat. No. 10,426,468), filed on Apr. 12, 2016, which claims the benefit of, and priority to, U.S. Provisional Patent Application No. 62/291,775, filed on Feb. 5, 2016, and U.S. Provisional Patent Application Nos. 62/151,145; 62/151,171; 62/151,183; 62/151,196; 62/151,206; 62/151,224; 62/151,235; 62/151,246; 62/151,255; 62/151,261; 62/151,266; and 62/151,273, each of which was filed on Apr. 22, 2015, the entire contents of each of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to surgical devices. More specifically, the present disclosure relates to handheld electromechanical surgical systems for performing surgical procedures. 
     2. Background of Related Art 
     One type of surgical device is a linear clamping, cutting and stapling device. 
     Such a device may be employed in a surgical procedure to resect a cancerous or anomalous tissue from a gastro-intestinal tract. Conventional linear clamping, cutting and stapling instruments include a pistol grip-styled structure having an elongated shaft and distal portion. The distal portion includes a pair of scissors-styled gripping elements, which clamp the open ends of the colon closed. In this device, one of the two scissors-styled gripping elements, such as the anvil portion, moves or pivots relative to the overall structure, whereas the other gripping element remains fixed relative to the overall structure. The actuation of this scissoring device (the pivoting of the anvil portion) is controlled by a grip trigger maintained in the handle. 
     In addition to the scissoring device, the distal portion also includes a stapling mechanism. The fixed gripping element of the scissoring mechanism includes a staple cartridge receiving region and a mechanism for driving the staples up through the clamped end of the tissue against the anvil portion, thereby sealing the previously opened end. The scissoring elements may be integrally formed with the shaft or may be detachable such that various scissoring and stapling elements may be interchangeable. 
     A number of surgical device manufacturers have developed product lines with proprietary powered drive systems for operating and/or manipulating the surgical device. In many instances the surgical devices include a powered handle assembly, which is reusable, and a disposable end effector or the like that is selectively connected to the powered handle assembly prior to use and then disconnected from the end effector following use in order to be disposed of or in some instances sterilized for re-use. 
     The use of powered electro and endomechanical surgical staplers, including intelligent battery power, has grown tremendously over the past few decades. Advanced technology and informatics within these intelligent battery-powered stapling devices provide the ability to gather clinical data and drive design improvements to ultimately improve patient outcomes. Accordingly, a need exists to evaluate conditions that affect staple formation with the intention of building a more intelligent stapling algorithm. 
     SUMMARY 
     In one aspect of the present disclosure, an adapter assembly is provided, which includes an elongate body, a switch actuator disposed within the elongate body, an actuator bar disposed within the elongate body, and a latch. The elongate body includes a proximal portion configured to couple to a handle assembly and a distal portion configured to couple to a surgical loading unit. The switch actuator is movable between a proximal position, in which the switch actuator actuates a switch, and a distal position. The actuation bar is movable between a proximal position and a distal position. The latch is associated with the switch actuator and the actuation bar and is movable between a first position, in which the latch permits proximal movement of the switch actuator, and a second position, in which the latch prevents proximal movement of the switch actuator. The latch is configured to move from the first position toward the second position in response to the actuation bar moving toward the proximal position. 
     In some embodiments, the adapter assembly may further include a distal link disposed distally of the switch actuator, and a biasing member disposed between the switch actuator and the distal link. Proximal movement of the distal link may compress the biasing member between the switch actuator and the distal link when the latch is in the second position. The actuation bar may be configured to move the latch toward the first position to unlock the switch actuator from the latch during movement of the actuation bar toward the distal position, such that the biasing member moves the switch actuator toward the proximal position to actuate the switch. 
     It is contemplated that the latch may include a projection extending from a distal portion thereof, and the actuation bar may include a tab extending from a distal portion thereof. The tab of the actuation bar may be configured to contact the projection of the latch upon the actuation bar moving toward the distal position. 
     It is envisioned that the latch may have a proximal portion defining a groove therein. A distal portion of the switch actuator may have a tab extending therefrom dimensioned for receipt in the groove of the proximal portion of the latch. 
     In some embodiments, the latch may be resiliently biased toward the second position. 
     It is contemplated that the latch may include a proximal portion operably associated with the switch actuator, and a distal portion operably associated with the actuation bar. 
     It is envisioned that the proximal portion of the latch may have a mating feature, and a distal portion of the switch actuator may have a mating feature. The mating feature of the switch actuator may be configured to detachably matingly engage with the mating feature of the latch when the latch is in the second position and the switch actuator is in the distal position. 
     In some embodiments, a distal portion of the latch may include a projection, and a distal portion of the actuation bar may include a projection such that the projection of the distal portion of the actuation bar contacts the projection of the distal portion of the latch during movement of the actuation bar toward the distal position to effect pivoting of the latch toward the first position. 
     It is contemplated that movement of the actuation bar toward the distal position may pivot the latch toward the first position to release the switch actuator from the latch. 
     It is envisioned that the adapter assembly may further include a biasing member coupled to the latch to resiliently bias the latch toward the second position. 
     In some embodiments, the adapter assembly may further include a release lever fixed to a proximal portion of the actuation bar to provide manual actuation of the actuation bar. 
     It is contemplated that both the switch actuator and the actuation bar may be resiliently biased toward their distal positions. 
     In another aspect of the present disclosure, an adapter assembly is provided, which includes an elongate body, a switch actuator disposed within the elongate body, a distal link, an actuation bar disposed within the elongate body, and a latch. The elongate body includes a proximal portion configured to couple to a handle assembly and a distal portion configured to couple to a surgical loading unit. The switch actuator is movable between a proximal position, in which the switch actuator actuates a switch, and a distal position. The distal link is disposed distally of the switch actuator and is operably coupled to the switch actuator. The actuation bar is movable between a proximal position and a distal position. The latch is associated with the switch actuator and the actuation bar and is movable between a first position, in which the latch permits proximal movement of the switch actuator, and a second position, in which the latch prevents proximal movement of the switch actuator. The latch is configured to move from the second position toward the first position in response to the actuation bar moving toward the distal position to allow the switch actuator to move relative to the distal link and toward the proximal position to actuate the switch. 
     In some embodiments, the adapter assembly may further include a biasing member disposed between the switch actuator and the distal link. Proximal movement of the distal link may compress the biasing member between the switch actuator and the distal link when the latch is in the second position. The actuation bar may be configured to move the latch toward the first position to unlock the switch actuator from the latch during movement of the actuation bar toward the distal position, such that the biasing member moves the switch actuator relative to the distal link and toward the proximal position to actuate the switch. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a handheld surgical device and adapter assembly, in accordance with an embodiment of the present disclosure, illustrating a connection thereof with an end effector; 
         FIG. 2  is a perspective view of the handheld surgical device of  FIG. 1 ; 
         FIG. 3  is a front perspective view, with parts separated, of the handheld surgical device of  FIGS. 1 and 2 ; 
         FIG. 4  is a rear perspective view, with parts separated, of the handheld surgical device of  FIGS. 1 and 2 ; 
         FIG. 5  is a perspective view illustrating insertion of a power-pack into an outer shell housing of the handheld surgical device; 
         FIG. 6  is a perspective view illustrating the power-pack nested into the outer shell housing of the handheld surgical device; 
         FIG. 7  is a side elevational view of the outer shell housing of the handheld surgical device; 
         FIG. 8  is a bottom perspective view of the outer shell housing of the handheld surgical device, and an insertion guide thereof; 
         FIG. 9  is an enlarged, bottom perspective view of the outer shell housing of the handheld surgical device with the insertion guide separated therefrom; 
         FIG. 10  is a first perspective view of the insertion guide; 
         FIG. 11  is a second perspective view of the insertion guide; 
         FIG. 12  is a front, perspective view of the power-pack with an inner rear housing separated therefrom; 
         FIG. 13  is a rear, perspective view of the power-pack with the inner rear housing removed therefrom; 
         FIG. 14  is a perspective view of a power-pack core assembly of the power-pack; 
         FIG. 15  is a front, perspective view of a motor assembly and a control assembly of the power-pack core assembly of  FIG. 14 ; 
         FIG. 16  is a rear, perspective view, with parts separated, of the motor assembly and the control assembly of  FIG. 15 ; 
         FIG. 17  is a longitudinal, cross-sectional view of the handheld surgical device of  FIG. 2 ; 
         FIG. 18  is an enlarged view of the indicated area of detail of  FIG. 17 ; 
         FIG. 19  is a cross-sectional view of the handheld surgical device as taken through  19 - 19  of  FIG. 17 ; 
         FIG. 20  is a front, perspective view of the adapter assembly of  FIG. 1 ; 
         FIG. 21  is a rear, perspective view of the adapter assembly of  FIGS. 1 and 20 ; 
         FIG. 22  is a perspective view illustrating a connection of the adapter assembly and the handheld surgical device; 
         FIG. 23  is a top, plan view of the adapter assembly of  FIGS. 1 and 20-22 ; 
         FIG. 24  is a side, elevational view of the adapter assembly of  FIGS. 1 and 20-23 ; 
         FIG. 25  is a perspective view, with parts separated, of the adapter assembly of  FIGS. 1 and 20-24 ; 
         FIG. 26  is a rear, perspective view of the adapter assembly of  FIGS. 1 and 20-25 , with most parts thereof separated; 
         FIG. 27  is a perspective view of an articulation assembly of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 28  is an enlarged, perspective view, with parts separated, of the articulation assembly of  FIG. 27 ; 
         FIG. 29  is a perspective view of the articulation assembly of  FIG. 27 , shown in a first orientation; 
         FIG. 30  is a perspective view of the articulation assembly of  FIG. 27 , shown in a second orientation; 
         FIG. 31  is a cross-sectional view of the articulation assembly of  FIG. 29 ; 
         FIG. 32  is a perspective view of an electrical assembly of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 33  is a perspective view of the electrical assembly shown supported on a proximal inner housing assembly; 
         FIG. 34  is a perspective view of a slip ring cannula or sleeve of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 35  is a cross-sectional view as taken along section line  35 - 35  of  FIG. 33 ; 
         FIG. 36  is a longitudinal, cross-sectional view of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 37  is an enlarged view of the indicated area of detail of  FIG. 21 ; 
         FIG. 38  is a rear, perspective view of the inner housing assembly of the adapter assembly of  FIGS. 1 and 20-26 , with an outer knob housing half-section and a proximal cap removed therefrom; 
         FIG. 39  is a rear, perspective view of the inner housing assembly of the adapter assembly of  FIGS. 1 and 20-26 , with the outer knob housing, the proximal cap and a bushing plate removed therefrom; 
         FIG. 40  is a rear, perspective view of the inner housing assembly of the adapter assembly of  FIGS. 1 and 20-26 , with the outer knob housing, the proximal cap, the bushing plate and an inner housing removed therefrom; 
         FIG. 41  is an enlarged view of the indicated area of detail of  FIG. 36 ; 
         FIG. 42  is an enlarged view of the indicated area of detail of  FIG. 36 , illustrating a lock button being actuated in a proximal direction; 
         FIG. 43  is a cross-sectional view as taken along section line  43 - 43  of  FIG. 37 ; 
         FIG. 44  is a longitudinal, cross-sectional view of the inner and outer knob housing of the adapter assembly, illustrating actuation of the articulation assembly in a distal direction; 
         FIG. 45  is a cross-sectional view as taken along section line  45 - 45  of  FIG. 44 ; 
         FIG. 46  is a cross-sectional view as taken along section line  46 - 46  of  FIG. 44 ; 
         FIG. 47  is a cross-sectional view as taken along section line  47 - 47  of  FIG. 44 ; 
         FIG. 48  is a cutaway view of a distal portion of the adapter assembly shown of  FIGS. 1 and 20-26 , without a loading unit engaged therewith; 
         FIG. 49  is a perspective view of an annular member of the adapter assembly of 
         FIGS. 1 and 20-26 ; 
         FIG. 50  is a perspective view of the annular member shown in  FIG. 49  electrically connected to a switch of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 51  is an enlarged view of the distal portion of the adapter assembly of  FIGS. 1 and 20-26 , including the annular member and the switch assembled therein; 
         FIG. 52  is another cutaway view of the distal portion of the adapter assembly of  FIGS. 1 and 20-26 , without a loading unit engaged therewith; 
         FIG. 53  is a perspective view of the loading unit of  FIG. 1 ; 
         FIG. 54  is a perspective view, with parts separated, of the loading unit of  FIGS. 1 and 53 ; 
         FIGS. 55 and 56  are alternate perspective views of an inner housing of the loading unit shown in  FIGS. 1 and 53-54 ; 
         FIGS. 57 and 58  are alternate cutaway views of the loading unit shown in  FIGS. 1 and 53-54 , with the inner and outer housings assembled; 
         FIGS. 59 and 60  are alternate cutaway views of an outer housing of the loading unit shown in  FIGS. 1 and 53-54 ; 
         FIGS. 61 and 62  are alternate cutaway views of the distal portion of the adapter assembly of  FIGS. 1 and 20-26  engaged with the loading unit, illustrating the annular member in a first orientation and a sensor link in a non-locking configuration; 
         FIGS. 63 and 64  are alternate cutaway views of the distal portion of the adapter assembly of  FIGS. 1 and 20-26  engaged with the loading unit, illustrating the annular member in a second orientation and the sensor link in a locking configuration; 
         FIG. 65  is an enlarged cutaway view of the distal portion of the adapter assembly of  FIGS. 1 and 20-26 ; 
         FIG. 66  is a cutaway view of the loading unit of  FIGS. 1 and 53-54  inserted into the annular member shown in  FIG. 49 ; 
         FIG. 67  is a cross-sectional view of the loading unit of  FIGS. 1 and 53-54 , taken along line  67 - 67  of  FIG. 66 ; 
         FIG. 68  is a cross-sectional view of the loading unit of  FIGS. 1 and 53-54 , taken along line  68 - 68  of  FIG. 66 ; 
         FIGS. 69A-69D  are perspective views of various other loading units configured for use with the handheld surgical device of  FIG. 1 ; 
         FIG. 70  is a schematic diagram of the circuit board of the power-pack of the handheld surgical device of  FIG. 1 ; 
         FIG. 71  is a block diagram of a simplified system hardware of the power-pack of the handheld surgical device of  FIG. 1 ; 
         FIG. 72  is a flow diagram of a method for controlling various modes of the power-pack of the handheld surgical device of  FIG. 1 ; 
         FIG. 73  is a flow diagram of a method of initializing the power-pack of the handheld surgical device of  FIG. 1 ; 
         FIG. 74  is a flow diagram of a portion of the method of initializing of  FIG. 73 ; 
         FIG. 75  is a flow diagram of another portion of the method of initializing of  FIG. 73 ; 
         FIG. 76  is a flow diagram of yet another portion of the method of initializing of  FIG. 73 ; 
         FIG. 77  is a flow diagram of a wire testing method of the method of initializing of  FIG. 73 ; 
         FIG. 78  is a flow diagram of a method of validating components of the handheld surgical device of  FIG. 1 ; 
         FIG. 79  is a flow diagram of a portion of the method of validating components of  FIG. 78 ; 
         FIG. 80  is a flow diagram of a method of calibrating components of the handheld surgical device of  FIG. 1 ; 
         FIG. 81  is a flow diagram of another method of calibrating of the handheld surgical device of  FIG. 1 ; 
         FIG. 82  is a block diagram of the operation module of the system hardware of  FIG. 71 ; 
         FIG. 83  is a side view of another embodiment of an adapter assembly for interconnecting a handheld surgical device and a loading unit of the present disclosure; 
         FIG. 84  is a perspective view, with outer housings removed, of the adapter assembly of  FIG. 83 ; 
         FIG. 85  is an enlarged view, with an outer housing removed, of a distal portion of the adapter assembly illustrating a switch actuation mechanism thereof in a pre-loaded state; 
         FIG. 86  is a side, perspective view of the adapter assembly of  FIG. 85  illustrating a loading unit inserted within the elongate body of the adapter assembly; 
         FIG. 87  is a side, perspective view of the adapter assembly and the loading unit of  FIG. 86  illustrating the switch actuation mechanism in a first loaded state; and 
         FIG. 88  is a side, perspective view of the adapter assembly and the loading unit of  FIG. 86  illustrating the switch actuation mechanism in a second loaded state. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Embodiments of the presently disclosed surgical devices, and adapter assemblies for surgical devices and/or handle assemblies are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein the term “distal” refers to that portion of the adapter assembly or surgical device, or component thereof, farther from the user, while the term “proximal” refers to that portion of the adapter assembly or surgical device, or component thereof, closer to the user. 
     A surgical device, in accordance with an embodiment of the present disclosure, is generally designated as  100 , and is in the form of a powered hand held electromechanical instrument configured for selective attachment thereto of a plurality of different end effectors that are each configured for actuation and manipulation by the powered hand held electromechanical surgical instrument. In addition to enabling powered actuation and manipulation, surgical device  100  further incorporates various safety and control features that help ensure proper, safe, and effective use thereof. 
     As illustrated in  FIG. 1 , surgical device is configured for selective connection with an adapter  200 , and, in turn, adapter  200  is configured for selective connection with end effectors or single use loading units (“SULU&#39;s”)  400 . Although described with respect to adapter  200  and SULU  400 , different adapters configured for use with different end effectors and/or different end effectors configured for use with adapter  200  are also capable of being used with surgical device  100 . Suitable end effectors configured for use with adapter  200  and/or other adapters usable with surgical device  100  include end effectors configured for performing endoscopic gastro-intestinal anastomosis (EGIA) procedures, e.g., SULU  400  and multi-use loading unit (“MULU”)  900 B (FIG.  69 B 1 ), end effectors configured to perform end-to-end anastomosis (EEA) procedures, e.g., loading unit  900 A ( FIG. 69A ), a transverse stapling loading units, e.g., loading unit  900 C ( FIG. 69C ), and curved loading units, e.g., loading unit  900 D ( FIG. 69D ). 
     As illustrated in  FIGS. 1-11 , surgical device  100  includes a power-pack  101 , and an outer shell housing  10  configured to selectively receive and sealingly encase power-pack  101  to establish a sterile barrier about power-pack  101 . Outer shell housing  10  includes a distal half-section  10   a  and a proximal half-section  10   b  pivotably connected to distal half-section  10   a  by a hinge  16  located along an upper edge of distal half-section  10   a  and proximal half-section  10   b . When joined, distal and proximal half-sections  10   a ,  10   b  define a shell cavity  10   c  therein in which power-pack  101  is selectively situated. 
     Distal and proximal half-sections  10   a ,  10   b  are divided along a plane that traverses a longitudinal axis “X” of adapter  200 . 
     Each of distal and proximal half-sections  10   a ,  10   b  includes a respective upper shell portion  12   a ,  12   b , and a respective lower shell portion  14   a ,  14   b . Lower shell portions  12   a ,  12   b  define a snap closure feature  18  for selectively securing lower shell portions  12   a ,  12   b  to one another and for maintaining outer shell housing  10  in a closed condition. 
     Distal half-section  10   a  of outer shell housing  10  defines a connecting portion  20  configured to accept a corresponding drive coupling assembly  210  of adapter  200 . Specifically, distal half-section  10   a  of outer shell housing  10  has a recess  20  that receives a portion of drive coupling assembly  210  of adapter  200  when adapter  200  is mated to surgical device  100 . 
     Connecting portion  20  of distal half-section  10   a  defines a pair of axially extending guide rails  20   a ,  20   b  projecting radially inward from inner side surfaces thereof. Guide rails  20   a ,  20   b  assist in rotationally orienting adapter  200  relative to surgical device  100  when adapter  200  is mated to surgical device  100 . 
     Connecting portion  20  of distal half-section  10   a  defines three apertures  22   a ,  22   b ,  22   c  formed in a distally facing surface thereof and which are arranged in a common plane or line with one another. Connecting portion  20  of distal half-section  10   a  also defines an elongate slot  24  (to contain connector  66 , see  FIG. 3 ) also formed in the distally facing surface thereof. 
     Connecting portion  20  of distal half-section  10   a  further defines a female connecting feature  26  (see  FIG. 2 ) formed in a surface thereof. Female connecting feature  26  selectively engages with a male connecting feature of adapter  200 , as will be described in greater detail below. 
     Distal half-section  10   a  of outer shell housing  10  supports a distal facing toggle control button  30 . Toggle control button  30  is capable of being actuated in a left, right, up and down direction upon application of a corresponding force thereto or a depressive force thereto. 
     Distal half-section  10   a  of outer shell housing  10  supports a right-side pair of control buttons  32   a ,  32   b ; and a left-side pair of control button  34   a ,  34   b . Right-side control buttons  32   a ,  32   b  and left-side control buttons  34   a ,  34   b  are capable of being actuated upon application of a corresponding force thereto or a depressive force thereto. 
     Proximal half-section  10   b  of outer shell housing  10  supports a right-side control button  36   a  and a left-side control button  36   b . Right-side control button  36   a  and left-side control button  36   b  are capable of being actuated upon application of a corresponding force thereto or a depressive force thereto. 
     Distal half-section  10   a  and proximal half-section  10   b  of outer shell housing  10  are fabricated from a polycarbonate or similar polymer, and are clear or transparent or may be overmolded. 
     With reference to  FIGS. 5-11 , surgical device  100  includes an insertion guide  50  that is configured and shaped to seat on and entirely surround a distal facing edge  10   d  ( FIGS. 3 and 9 ) of proximal half-section  10   b . Insertion guide  50  includes a body portion  52  having a substantially U-shaped transverse cross-sectional profile, and a stand-off  54  extending from a bottom of body portion  52 . Stand-off  54  is configured to engage snap closure feature  18  of each of lower shell portions  12   a ,  12   b  of respective distal and proximal half-sections  10   a ,  10   b  of outer shell housing  10 . 
     In use, when body portion  52  of insertion guide  50  is seated on distal facing edge  10   d  of proximal half-section  10   b , snap closure feature  18  of lower shell portion  12   a  of distal half-section  10   a  engages a first end of stand-off  54 , and snap closure feature  18  of lower shell portion  12   b  of proximal half-section  10   b  engages a first end of stand-off  54 . 
     With reference to  FIGS. 2-4 , outer shell housing  10  includes a sterile barrier plate assembly  60  selectively supported in distal half-section  10   a . Specifically, sterile barrier plate assembly  60  is disposed behind connecting portion  20  of distal half-section  10   a  and within shell cavity  10   c  of outer shell housing  10 . Plate assembly  60  includes a plate  62  rotatably supporting three coupling shafts  64   a ,  64   b ,  64   c . Each coupling shaft  64   a ,  64   b ,  64   c  extends from opposed sides of plate  62  and has a tri-lobe transverse cross-sectional profile. Each coupling shaft  64   a ,  64   b ,  64   c  extends through a respective aperture  22   a ,  22   b ,  22   c  of connecting portion  20  of distal half-section  10   a  when sterile barrier plate assembly  60  is disposed within shell cavity  10   c  of outer shell housing  10 . 
     Plate assembly  60  further includes an electrical pass-through connector  66  supported on plate  62 . Pass-through connector  66  extends from opposed sides of plate  62 . Each coupling shaft  64   a ,  64   b ,  64   c  extends through aperture  24  of connecting portion  20  of distal half-section  10   a  when sterile barrier plate assembly  60  is disposed within shell cavity  10   c  of outer shell housing  10 . Pass-through connector  66  defines a plurality of contact paths each including an electrical conduit for extending an electrical connection across plate  62 . The various communications relayed across pass-through connector  66  are described in detail below with respect to  FIGS. 70-82 . 
     When plate assembly  60  is disposed within shell cavity  10   c  of outer shell housing  10 , distal ends of coupling shaft  64   a ,  64   b ,  64   c  and a distal end of pass-through connector  66  are disposed or situated within connecting portion  20  of distal half-section  10   a  of outer shell housing  10 , and electrically and/or mechanically engage respective corresponding features of adapter  200 , as will be described in greater detail below. 
     In operation, with a new and/or sterile outer shell housing  10  in an open configuration (i.e., distal half-section  10   a  separated from proximal half-section  10   b , about hinge  16 ), and with insertion guide  50  in place against the distal edge of proximal half-section  10   b  of outer shell housing  10 , power-pack  101  is inserted into shell cavity  10   c  of outer shell housing  10 . With power-pack  101  inserted into shell cavity  10   c  of outer shell housing  10 , insertion guide  50  is removed from proximal half-section  10   b  and distal half-section  10   a  is pivoted, about hinge  16 , to a closed configuration for outer shell housing  10 . In the closed configuration, snap closure feature  18  of lower shell portion  12   a  of distal half-section  10   a  engages snap closure feature  18  of lower shell portion  12   b  of proximal half-section  10   b.    
     In operation, following a surgical procedure, snap closure feature  18  of lower shell portion  12   a  of distal half-section  10   a  is disengaged from snap closure feature  18  of lower shell portion  12   b  of proximal half-section  10   b , and distal half-section  10   a  is pivoted, about hinge  16 , away from proximal half-section  10   b  to open outer shell housing  10 . With outer shell housing  10  open, power-pack  101  is removed from shell cavity  10   c  of outer shell housing  10  (specifically from proximal half-section  10   b  of outer shell housing  10 ), and outer shell housing  10  is discarded. Power-pack  101  is then disinfected and cleaned. Power-pack  101  is not to be submerged or sterilized. 
     Outer shell housing  10 , in addition to aseptically sealing power-pack  101  when engaged thereabout, providing an operational interface for enabling operation of surgical device  100  from the exterior of outer shell housing  10 , and including electrical and mechanical pass-through features for transmitting control and drive signals between power-pack  101  and the other components of surgical device  100 , further includes a memory chip, e.g., a 1-wire chip, embedded therein. The memory chip includes a memory that stores a unique ID associated with outer shell housing  10  and is capable of being updated to mark outer shell housing  10  as “used.” The unique ID of outer shell housing  10  allows for exclusive pairing of outer shell housing  10  with a power-pack  101 , while the ability to mark outer shell housing  10  as “used” inhibits reuse of outer shell housing  10 , even with the same power-pack  101 . Electrical contacts associated with the outer shell housing  10  form part of a 1-wire bus  171  ( FIG. 70 ), or other suitable communication channel, that enables communication between power-pack  101  and the 1-wire chip of outer shell housing  10 . These features will be described in greater detail below with reference to  FIGS. 70-82 . The 1-wire chip of outer shell housing  10 , for example, may be disposed on or within plate assembly  60  thus enabling access thereto via one of the contact paths defined via pass-through connector  66 . Although other locations and/or electrical couplings for enabling communication between the 1-wire chip of outer shell housing  10  and power-pack  101  are also contemplated. 
     Referring to  FIGS. 3-6  and  FIGS. 12-19 , power-pack  101  includes an inner handle housing  110  having a lower housing portion  104  and an upper housing portion  108  extending from and/or supported on lower housing portion  104 . Lower housing portion  104  and upper housing portion  108  are separated into a distal half-section  110   a  and a proximal half-section  110   b  connectable to distal half-section  110   a  by a plurality of fasteners. When joined, distal and proximal half-sections  110   a ,  110   b  define an inner handle housing  110  having an inner housing cavity  110   c  therein in which a power-pack core assembly  106  is situated. 
     Power-pack core assembly  106  is configured to control the various operations of surgical device  100 , as will be set forth in additional detail below. 
     Distal half-section  110   a  of inner handle housing  110  defines a distal opening  111   a  therein which is configured and adapted to support a control plate  160  of power-pack core assembly  106 . Control plate  160  of power-pack  101  abuts against a rear surface of plate  62  of sterile barrier plate assembly  60  of outer shell housing  10  when power-pack  101  is disposed within outer shell housing  10 . 
     With reference to  FIG. 12 , distal half-section  110   a  of inner handle housing  110  supports a distal toggle control interface  130  that is in operative registration with distal toggle control button  30  of outer shell housing  10 . In use, when power-pack  101  is disposed within outer shell housing  10 , actuation of toggle control button  30  exerts a force on toggle control interface  130 . 
     Distal half-section  110   a  of inner handle housing  110  also supports a right-side pair of control interfaces  132   a ,  132   b , and a left-side pair of control interfaces  134   a ,  134   b . In use, when power-pack  101  is disposed within outer shell housing  10 , actuation of one of the right-side pair of control buttons  32   a ,  32   b  or the left-side pair of control button  34   a ,  34   b  of distal half-section  10   a  of outer shell housing  10  exerts a force on a respective one of the right-side pair of control interfaces  132   a ,  132   b  or the left-side pair of control interfaces  134   a ,  134   b  of distal half-section  110   a  of inner handle housing  110 . 
     In use, right-side pair of control interfaces  132   a ,  132   b  or the left-side pair of control interfaces  134   a ,  134   b  of distal half-section  110   a  of inner handle housing  110  will be deactivate or fail to function unless outer shell housing  10  has been validated. 
     Proximal half-section  110   b  of inner handle housing  110  defines a right-side control aperture  136   a  and a left-side control aperture  136   b . In use, when power-pack  101  is disposed within outer shell housing  10 , actuation of one of the right-side control button  36   a  or the left-side control button  36   b  of proximal half-section  10   b  of outer shell housing  10  extends the right-side control button  36   a  or the left-side control button  36   b  into and across the right-side control aperture  136   a  or the left-side control aperture  136   b  of the proximal half-section  110   b  of inner handle housing  110 . 
     With reference to  FIGS. 12-19 , inner handle housing  110  provides a housing in which power-pack core assembly  106  is situated. Power-pack core assembly  106  includes a rechargeable battery  144  configured to supply power to any of the electrical components of surgical device  100 , a battery circuit board  140 , and a controller circuit board  142 . Controller circuit board  142  includes a motor controller circuit board  142   a , a main controller circuit board  142   b , and a first ribbon cable  142   c  interconnecting motor controller circuit board  142   a  and main controller circuit board  142   b . The motor controller circuit board  142   a  is communicatively coupled with the battery circuit board  140  enabling communication therebetween and between the battery circuit board  140  and the main controller circuit board  142   b.    
     Power-pack core assembly  106  further includes a display screen  146  supported on main controller circuit board  142   b . Display screen  146  is visible through a clear or transparent window  110   d  (see  FIGS. 12 and 17 ) provided in proximal half-section  110   b  of inner handle housing  110 . It is contemplated that at least a portion of inner handle housing  110  may be fabricated from a transparent rigid plastic or the like. It is further contemplated that outer shell housing  10  may either include a window formed therein (in visual registration with display screen  146  and with window  110   d  of proximal half-section  110   b  of inner handle housing  110 , and/or outer shell housing  10  may be fabricated from a transparent rigid plastic or the like. 
     Power-pack core assembly  106  further includes a first motor  152 , a second motor  154 , and a third motor  156  each electrically connected to controller circuit board  142  and battery  144 . Motors  152 ,  154 ,  156  are disposed between motor controller circuit board  142   a  and main controller circuit board  142   b . Each motor  152 ,  154 ,  156  includes a respective motor shaft  152   a ,  154   a ,  156   a  extending therefrom. Each motor shaft  152   a ,  154   a ,  156   a  has a tri-lobe transverse cross-sectional profile for transmitting rotative forces or torque. As an alternative to motors  152 ,  154 ,  156 , it is envisioned that more or fewer motors be provided or that one or more other drive components be utilized, e.g., a solenoid, and controlled by appropriate controllers. Manual drive components are also contemplated. 
     Each motor  152 ,  154 ,  156  is controlled by a respective motor controller “MC 0 ,” MC 1 ,” “MC 2 .” Motor controllers “MC 0 ,” MC 1 ,” “MC 2 ” are disposed on the motor controller circuit board  142   a . The motor controllers are disposed on motor controller circuit board  142   a  and are, for example, A3930/31K motor drivers from Allegro Microsystems, Inc. The A3930/31K motor drivers are designed to control a 3-phase brushless DC (BLDC) motor with N-channel external power MOSFETs, such as the motors  152 ,  154 ,  156 . Each of the motor controllers is coupled to a main controller or master chip  157  disposed on the main controller circuit board  142   b  via first ribbon cable  142   c  which connects the motor controller circuit board  142   a  with the main controller circuit board  142   b . The main controller  157  communicates with motor controllers “MC 0 ,” MC 1 ,” “MC 2 ” through a field-programmable gate array (FPGA)  162 , which provides control logic signals (e.g., coast, brake, etc.). The control logic of motor controllers “MC 0 ,” MC 1 ,” “MC 2 ” then outputs corresponding energization signals to respective motor  152 ,  154 ,  156  using fixed-frequency pulse width modulation (PWM). The main controller  157  is also coupled to memory  165 , which is also disposed on the main controller circuit board  142   b . The main controller  157  is, for example, an ARM Cortex M4 processor from Freescale Semiconductor, Inc, which includes  1024  kilobytes of internal flash memory. 
     Each motor  152 ,  154 ,  156  is supported on a motor bracket  148  such that motor shaft  152   a ,  154   a ,  156   a  are rotatably disposed within respective apertures of motor bracket  148 . As illustrated in  FIGS. 16 and 19 , motor bracket  148  rotatably supports three rotatable drive connector sleeves  152   b ,  154   b ,  156   b  that are keyed to respective motor shafts  152   a ,  154   a ,  156   a  of motors  152 ,  154 ,  156 . Drive connector sleeves  152   b ,  154   b ,  156   b  non-rotatably receive proximal ends of respective coupling shaft  64   a ,  64   b ,  64   c  of plate assembly  60  of outer shell housing  10 , when power-pack  101  is disposed within outer shell housing  10 . Drive connector sleeves  152   b ,  154   b ,  156   b  are each spring biased away from respective motors  152 ,  154 ,  156 . 
     Rotation of motor shafts  152   a ,  154   a ,  156   a  by respective motors  152 ,  154 ,  156  function to drive shafts and/or gear components of adapter  200  in order to perform the various operations of surgical device  100 . In particular, motors  152 ,  154 ,  156  of power-pack core assembly  106  are configured to drive shafts and/or gear components of adapter  200  in order to selectively move tool assembly  404  of SULU  400  relative to proximal body portion  402  of SULU  400 , to rotate SULU  400  about a longitudinal axis “X,” to move cartridge assembly  408  relative to anvil assembly  406  of SULU  400 , and/or to fire staples from within cartridge assembly  408  of SULU  400 . 
     Motor bracket  148  also supports an electrical adapter interface receptacle  149 . Electrical receptacle  149  is in electrical connection with main controller circuit board  142   b  by a second ribbon cable  142   d . Electrical receptacle  149  defines a plurality of electrical slots for receiving respective electrical contacts or blades extending from pass-through connector  66  of plate assembly  60  of outer shell housing  10 . 
     In use, when adapter  200  is mated to surgical device  100 , each of coupling shaft  64   a ,  64   b ,  64   c  of plate assembly  60  of outer shell housing  10  of surgical device  100  couples with a corresponding rotatable connector sleeves  218 ,  220 ,  222  of adapter  200  (see  FIG. 22 ). In this regard, the interface between corresponding first coupling shaft  64   a  and first connector sleeve  218 , the interface between corresponding second coupling shaft  64   b  and second connector sleeve  220 , and the interface between corresponding third coupling shaft  64   c  and third connector sleeve  222  are keyed such that rotation of each of coupling shafts  64   a ,  64   b ,  64   c  of surgical device  100  causes a corresponding rotation of the corresponding connector sleeve  218 ,  220 ,  222  of adapter  200 . The identification, verification, and other communications between power-pack  101  and adapter  200  upon engagement therebetween are detailed below with respect to  FIGS. 70-82 . 
     The mating of coupling shafts  64   a ,  64   b ,  64   c  of surgical device  100  with connector sleeves  218 ,  220 ,  222  of adapter  200  allows rotational forces to be independently transmitted via each of the three respective connector interfaces. The coupling shafts  64   a ,  64   b ,  64   c  of surgical device  100  are configured to be independently rotated by respective motors  152 ,  154 ,  156 . 
     Since each of coupling shafts  64   a ,  64   b ,  64   c  of surgical device  100  has a keyed and/or substantially non-rotatable interface with respective connector sleeves  218 ,  220 ,  222  of adapter  200 , when adapter  200  is coupled to surgical device  100 , rotational force(s) are selectively transferred from motors  152 ,  154 ,  156  of surgical device  100  to adapter  200 . 
     The selective rotation of coupling shaft(s)  64   a ,  64   b ,  64   c  of surgical device  100  allows surgical device  100  to selectively actuate different functions of SULU  400 . As will be discussed in greater detail below, selective and independent rotation of first coupling shaft  64   a  of surgical device  100  corresponds to the selective and independent opening and closing of tool assembly  404  of SULU  400 , and driving of a stapling/cutting component of tool assembly  404  of SULU  400 . Also, the selective and independent rotation of second coupling shaft  64   b  of surgical device  100  corresponds to the selective and independent articulation of tool assembly  404  of SULU  400  transverse to longitudinal axis “X” (see  FIG. 21 ). Additionally, the selective and independent rotation of third coupling shaft  64   c  of surgical device  100  corresponds to the selective and independent rotation of SULU  400  about longitudinal axis “X” (see  FIG. 21 ) relative to surgical device  100 . 
     With reference to  FIGS. 12-19 , power-pack core assembly  106  further includes a switch assembly  170  supported within distal half-section  110   a  of inner handle housing  110 , at a location beneath and in registration with toggle control interface  130 , the right-side pair of control interfaces  132   a ,  132   b , and the left-side pair of control interfaces  134   a ,  134   b . Switch assembly  170  includes a first set of four push-button switches  172   a - 172   d  arranged around stem  30   a  of toggle control button  30  of outer shell housing  10  when power-pack  101  is disposed within outer shell housing  10 . Switch assembly  170  also includes a second pair of push-button switches  174   a ,  174   b  disposed beneath right-side pair of control interfaces  132   a ,  132   b  of distal half-section  110   a  of inner handle housing  110  when power-pack  101  is disposed within outer shell housing  10 . Switch assembly  170  further includes a third pair of push-button switches  176   a ,  176   b  disposed beneath left-side pair of control interfaces  134   a ,  134   b  of distal half-section  110   a  of inner handle housing  110  when power-pack  101  is disposed within outer shell housing  10 . 
     Power-pack core assembly  106  includes a single right-side push-button switch  178   a  disposed beneath right-side control aperture  136   a  of proximal half-section  110   b  of inner handle housing  110 , and a single left-side push-button switch  178   b  disposed beneath left-side control aperture  136   b  of proximal half-section  110   b  of inner handle housing  110 . Push-button switches  178   a ,  178   b  are supported on controller circuit board  142 . Push-button switches  178   a ,  178   b  are disposed beneath right-side control button  36   a  and left-side control button  36   b  of proximal half-section  10   b  of outer shell housing  10  when power-pack  101  is disposed within outer shell housing  10 . Actuation of right or left-side control button  36   a ,  36   b  actuates the respective right or left safety switches or keys  178   a ,  178   b  to permit entry of power-pack core assembly  106  into the firing state. Entry into the firing state instructs surgical device  100  that SULU  400  is ready to expel fasteners therefrom. 
     The actuation of push button switch  172   c , corresponding to a downward actuation of toggle control button  30 , causes controller circuit board  142  to provide appropriate signals to motor  152  to close a tool assembly  404  of SULU  400  and/or to fire staples from within cartridge assembly  408  of SULU  400 . 
     The actuation of push button switch  172   a , corresponding to an upward actuation of toggle control button  30 , causes controller circuit board  142  to provide appropriate signals to motor  152  to retract a staple sled and open tool assembly  404  of SULU  400 . 
     The actuation of push button  172   d , corresponding to an actuation of toggle control button  30  to the right, causes controller circuit board  142  to provide appropriate signals to motor  152  to articulate tool assembly  404  to the right relative to body portion  402  of SULU  400 . Similarly, the actuation of push button  172   b , corresponding to an actuation of toggle control button  30  to the left, causes controller circuit board  142  to provide appropriate signals to motor  152  to articulate tool assembly  404  to the left relative to body portion  402  of SULU  400 . 
     The actuation of switches  174   a ,  174   b  (by right-hand thumb of user) or switches  176   a ,  176   b  (by left-hand thumb of user), corresponding to respective actuation of right-side pair of control buttons  32   a ,  32   b  or left-side pair of control button  34   a ,  34   b , causes controller circuit board  142  to provide appropriate signals to motor  154  to rotate SULU  400  relative to surgical device  100 . Specifically, actuation of control button  32   a  or  34   a  causes SULU  400  to rotate relative to surgical device  100  in a first direction, while actuation of control button  32   b  or  34   b  causes SULU  400  to rotate relative to surgical device  100  in an opposite, e.g., second, direction. 
     In use, tool assembly  404  of SULU  400  is actuated between opened and closed conditions as needed and/or desired. In order to fire SULU  400 , to expel fasteners therefrom, when tool assembly  404  of SULU  400  is in a closed condition, safety switch  178   a  or  178   b  is depressed thereby instructing surgical device  100  that SULU  400  is ready to expel fasteners therefrom. 
     With reference to  FIGS. 12 and 14 , power-pack core assembly  106  of surgical device  100  includes a USB connector  180  supported on main controller circuit board  142   b  of controller circuit board  142 . USB connector  180  is accessible through control plate  160  of power-pack core assembly  106 . When power-pack  101  is disposed within outer shell housing  10 , USB connector  180  is covered by plate  62  of sterile barrier plate assembly  60  of outer shell housing  10 . 
     As illustrated in  FIG. 1  and  FIGS. 20-52 , surgical device  100  is configured for selective connection with one or more different types of adapters, e.g., adapter  200 , and, in turn, the adapter  200  is configured for selective connection with one or more different types of loading units, e.g., SULU  400 , a loading unit  900  ( FIG. 69 ), a multi-use loading unit (MULU) having a configuration similar to that of SULU  400  or loading unit  900  ( FIG. 69 ), etc. 
     Adapter  200  is configured to convert a rotation of either of drive connector sleeve  152   b  or  156   b  of surgical device  100  into axial translation useful for operating a drive assembly  460  and an articulation link  466  of SULU  400 , as illustrated in  FIG. 54 , and as will be discussed in greater detail below. 
     Adapter  200  includes a first drive transmitting/converting assembly for interconnecting first drive connector sleeve  152   a  of surgical device  100  and a first axially translatable drive member of SULU  400 , wherein the first drive transmitting/converting assembly converts and transmits a rotation of first drive connector sleeve  152   a  of surgical device  100  to an axial translation of the first axially translatable drive assembly  460  of SULU  400  for firing. 
     Adapter  200  includes a second drive transmitting/converting assembly for interconnecting third drive connector sleeve  156   b  of surgical device  100  and a second axially translatable drive member of SULU  400 , wherein the second drive transmitting/converting assembly converts and transmits a rotation of third drive connector sleeve  156   b  of surgical device  100  to an axial translation of articulation link  466  of SULU  400  for articulation. 
     Turning now to  FIGS. 21-47 , adapter  200  includes an outer knob housing  202  and an outer tube  206  extending from a distal end of knob housing  202 . Knob housing  202  and outer tube  206  are configured and dimensioned to house the components of adapter assembly  200 . Outer tube  206  is dimensioned for endoscopic insertion, in particular, that outer tube is passable through a typical trocar port, cannula or the like. Knob housing  202  is dimensioned to not enter the trocar port, cannula of the like. Knob housing  202  is configured and adapted to connect to connecting portion  108  of handle housing  102  of surgical device  100 . 
     Adapter  200  is configured to convert a rotation of either of first or second coupling shafts  64   a ,  64   b  of surgical device  100  into axial translation useful for operating a drive assembly  460  and an articulation link  466  of SULU  400 , as illustrated in  FIG. 54  and as will be described in greater detail below. As illustrated in  FIGS. 26 and 38-47 , adapter  200  includes a proximal inner housing assembly  204  rotatably supporting a first rotatable proximal drive shaft  212 , a second rotatable proximal drive shaft  214 , and a third rotatable proximal drive shaft  216  therein. Each proximal drive shaft  212 ,  214 ,  216  functions as a rotation receiving member to receive rotational forces from respective coupling shafts  64   a ,  64   b  and  64   c  of surgical device  100 , as described in greater detail below. 
     As described briefly above, drive coupling assembly  210  of adapter  200  is also configured to rotatably support first, second and third connector sleeves  218 ,  222  and  220 , respectively, arranged in a common plane or line with one another. Each of connector sleeves  218 ,  222 ,  220  is configured to mate with respective first, second and third coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100 , as described above. Each of connector sleeves  218 ,  222 ,  220  is further configured to mate with a proximal end of respective first, second and third proximal drive shafts  212 ,  214 ,  216  of adapter  200 . 
     Drive coupling assembly  210  of adapter  200  also includes, as illustrated in  FIGS. 26, 38 and 41-44 , a first, a second and a third biasing member  224 ,  226  and  228  disposed distally of respective first, second and third connector sleeves  218 ,  220 ,  222 . Each of biasing members  224 ,  226  and  228  is disposed about respective first, second and third rotatable proximal drive shaft  212 ,  214  and  216 . Biasing members  224 ,  226  and  228  act on respective connector sleeves  218 ,  222  and  220  to help maintain connector sleeves  218 ,  222  and  220  engaged with the distal end of respective coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100  when adapter  200  is connected to surgical device  100 . 
     In particular, first, second and third biasing members  224 ,  226  and  228  function to bias respective connector sleeves  218 ,  222  and  220  in a proximal direction. In this manner, during connection of surgical device  100  when adapter  200  to surgical device  100 , if first, second and or third connector sleeves  218 ,  222  and/or  220  is/are misaligned with coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100 , first, second and/or third biasing member(s)  224 ,  226  and/or  228  are compressed. Thus, when surgical device  100  is operated, coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100  will rotate and first, second and/or third biasing member(s)  224 ,  226  and/or  228  will cause respective first, second and/or third connector sleeve(s)  218 ,  222  and/or  220  to slide back proximally, effectively connecting coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100  to first, second and/or third proximal drive shaft(s)  212 ,  214  and  216  of drive coupling assembly  210 . 
     Adapter  200  includes a plurality of force/rotation transmitting/converting assemblies, each disposed within inner housing assembly  204  and outer tube  206 . Each force/rotation transmitting/converting assembly is configured and adapted to transmit/convert a speed/force of rotation (e.g., increase or decrease) of first, second and third rotatable coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100  before transmission of such rotational speed/force to SULU  400 . 
     Specifically, as illustrated in  FIG. 26 , adapter  200  includes a first, a second and a third force/rotation transmitting/converting assembly  240 ,  250 ,  260 , respectively, disposed within inner housing assembly  204  and outer tube  206 . Each force/rotation transmitting/converting assembly  240 ,  250 ,  260  is configured and adapted to transmit or convert a rotation of a first, second and third coupling shafts  64   a ,  64   c  and  64   b  of surgical device  100  into axial translation of articulation bar  258  of adapter  200 , to effectuate articulation of SULU  400 ; a rotation of a ring gear  266  of adapter  200 , to effectuate rotation of adapter  200 ; or axial translation of a distal drive member  248  of adapter  200  to effectuate closing, opening and firing of SULU  400 . 
     As shown in  FIGS. 26 and 41-45 , first force/rotation transmitting/converting assembly  240  includes first rotatable proximal drive shaft  212 , which, as described above, is rotatably supported within inner housing assembly  204 . First rotatable proximal drive shaft  212  includes a non-circular or shaped proximal end portion configured for connection with first connector  218  which is connected to respective first coupling shaft  64   a  of surgical device  100 . First rotatable proximal drive shaft  212  includes a distal end portion  212   b  having a threaded outer profile or surface. 
     First force/rotation transmitting/converting assembly  240  further includes a drive coupling nut  244  rotatably coupled to threaded distal end portion  212   b  of first rotatable proximal drive shaft  212 , and which is slidably disposed within outer tube  206 . Drive coupling nut  244  is slidably keyed within proximal core tube portion of outer tube  206  so as to be prevented from rotation as first rotatable proximal drive shaft  212  is rotated. In this manner, as first rotatable proximal drive shaft  212  is rotated, drive coupling nut  244  is translated along threaded distal end portion  212   b  of first rotatable proximal drive shaft  212  and, in turn, through and/or along outer tube  206 . 
     First force/rotation transmitting/converting assembly  240  further includes a distal drive member  248  that is mechanically engaged with drive coupling nut  244 , such that axial movement of drive coupling nut  244  results in a corresponding amount of axial movement of distal drive member  248 . The distal end portion of distal drive member  248  supports a connection member  247  configured and dimensioned for selective engagement with a drive member  474  of drive assembly  460  of SULU  400  ( FIG. 54 ). Drive coupling nut  244  and/or distal drive member  248  function as a force transmitting member to components of SULU  400 , as described in greater detail below. 
     In operation, as first rotatable proximal drive shaft  212  is rotated, due to a rotation of first connector sleeve  218 , as a result of the rotation of first coupling shaft  64   a  of surgical device  100 , drive coupling nut  244  is caused to be translated axially along first distal drive shaft  242 . As drive coupling nut  244  is caused to be translated axially along first distal drive shaft  242 , distal drive member  248  is caused to be translated axially relative to outer tube  206 . As distal drive member  248  is translated axially, with connection member  247  connected thereto and engaged with drive member  474  of drive assembly  460  of SULU  400  ( FIG. 54 ), distal drive member  248  causes concomitant axial translation of drive member  474  of SULU  400  to effectuate a closure of tool assembly  404  and a firing of tool assembly  404  of SULU  400 . 
     With reference to  FIGS. 26-31, 45 and 46 , second drive converter assembly  250  of adapter  200  includes second proximal drive shaft  214  rotatably supported within inner housing assembly  204 . Second rotatable proximal drive shaft  214  includes a non-circular or shaped proximal end portion configured for connection with second connector or coupler  222  which is connected to respective second coupling shaft  64   c  of surgical device  100 . Second rotatable proximal drive shaft  214  further includes a distal end portion  214   b  having a threaded outer profile or surface. 
     Distal end portion  214   a  of proximal drive shaft  214  is threadably engaged with an articulation bearing housing  252   a  of an articulation bearing assembly  252 . Articulation bearing assembly  252  includes a housing  252   a  supporting an articulation bearing  253  having an inner race  253   b  that is independently rotatable relative to an outer race  253   a . Articulation bearing housing  252   a  has a non-circular outer profile, for example tear-dropped shaped, that is slidably and non-rotatably disposed within a complementary bore  204   c  ( FIGS. 45 and 46 ) of inner housing hub  204   a.    
     Second drive converter assembly  250  of adapter  200  further includes an articulation bar  258  having a proximal portion  258   a  secured to inner race  253   b  of articulation bearing  253 . A distal portion  258   b  of articulation bar  258  includes a slot  258   c  therein, which is configured to accept a flag of the articulation link  466  ( FIG. 54 ) of SULU  400 . Articulation bar  258  functions as a force transmitting member to components of SULU  400 , as described in greater detail below. 
     With further regard to articulation bearing assembly  252 , articulation bearing assembly  252  is both rotatable and longitudinally translatable. Additionally, it is envisioned that articulation bearing assembly  252  allows for free, unimpeded rotational movement of SULU  400  when its jaw members  406 ,  408  are in an approximated position and/or when jaw members  406 ,  408  are articulated. 
     In operation, as second proximal drive shaft  214  is rotated due to a rotation of second connector sleeve  222 , as a result of the rotation of the second coupling shaft  64   c  of surgical device  100 , articulation bearing assembly  252  is caused to be translated axially along threaded distal end portion  214   b  of second proximal drive shaft  214 , which in turn causes articulation bar  258  to be axially translated relative to outer tube  206 . As articulation bar  258  is translated axially, articulation bar  258 , being coupled to articulation link  466  of SULU  400 , causes concomitant axial translation of articulation link  466  of SULU  400  to effectuate an articulation of tool assembly  404 . Articulation bar  258  is secured to inner race  253   b  of articulation bearing  253  and is thus free to rotate about the longitudinal axis X-X relative to outer race  253   a  of articulation bearing  253 . 
     As illustrated in  FIGS. 26, 38, 39, 43, 44 and 47 , and as described, adapter  200  includes a third force/rotation transmitting/converting assembly  260  supported in inner housing assembly  204 . Third force/rotation transmitting/converting assembly  260  includes a rotation ring gear  266  fixedly supported in and connected to outer knob housing  202 . Ring gear  266  defines an internal array of gear teeth  266   a  ( FIG. 26 ). Ring gear  266  includes a pair of diametrically opposed, radially extending protrusions  266   b  ( FIG. 26 ) projecting from an outer edge thereof. Protrusions  266   b  are disposed within recesses defined in outer knob housing  202 , such that rotation of ring gear  266  results in rotation of outer knob housing  202 , and vice a versa. 
     Third force/rotation transmitting/converting assembly  260  further includes third rotatable proximal drive shaft  216  which, as described above, is rotatably supported within inner housing assembly  204 . Third rotatable proximal drive shaft  216  includes a non-circular or shaped proximal end portion configured for connection with third connector  220  which is connected to respective third connector  122  of surgical device  100 . Third rotatable proximal drive shaft  216  includes a spur gear  216   a  keyed to a distal end thereof. A reversing spur gear  264  inter-engages spur gear  216   a  of third rotatable proximal drive shaft  216  to gear teeth  266   a  of ring gear  266 . 
     In operation, as third rotatable proximal drive shaft  216  is rotated, due to a rotation of third connector sleeve  220 , as a result of the rotation of the third coupling shaft  64   b  of surgical device  100 , spur gear  216   a  of third rotatable proximal drive shaft  216  engages reversing gear  264  causing reversing gear  264  to rotate. As reversing gear  264  rotates, ring gear  266  also rotates thereby causing outer knob housing  202  to rotate. As outer knob housing  202  is rotated, outer tube  206  is caused to be rotated about longitudinal axis “X” of adapter  200 . As outer tube  206  is rotated, SULU  400 , that is connected to a distal end portion of adapter  200 , is also caused to be rotated about a longitudinal axis of adapter  200 . 
     Adapter  200  further includes, as seen in  FIGS. 22-25 , an attachment/detachment button  272  supported thereon. Specifically, button  272  is supported on a stem  273  ( FIGS. 25, 26, 41 and 42 ) projecting from drive coupling assembly  210  of adapter  200 , and is biased by a biasing member  274 , disposed within or around stem  273 , to an un-actuated condition. Button  272  includes a lip or ledge  272   a  formed therewith that is configured to snap behind a corresponding lip or ledge  108   b  defined along recess  108   a  of connecting portion  108  of handle housing  102  of surgical device  100 . While stem  273  is illustrated as having a relatively longer length to improve/increase stability of button  272  during actuation, it is envisioned that stem  273  may have a relatively shorter length than the length depicted. 
     In use, when adapter  200  is connected to surgical device  100 , lip  272   a  of button  272  is disposed behind lip  108   b  of connecting portion  108  of handle housing  102  of surgical device  100  to secure and retain adapter  200  and surgical device  100  with one another. In order to permit disconnection of adapter  200  and surgical device  100  from one another, button  272  is depressed or actuated, against the bias of biasing member  274 , to disengage lip  272   a  of button  272  and lip  108   b  of connecting portion  108  of handle housing  102  of surgical device  100 . 
     With reference to  FIGS. 23-25 and 48-52 , adapter  200  further includes a lock mechanism  280  for fixing the axial position of distal drive member  248 . Lock mechanism  280  includes a button  282  slidably supported on outer knob housing  202 . Lock button  282  is connected to an actuation bar  284  that extends longitudinally through outer tube  206 . Actuation bar  284  moves upon a movement of lock button  282 . 
     In operation, in order to lock the position and/or orientation of distal drive member  248 , a user moves lock button  282  from a distal position to a proximal position ( FIGS. 25 and 41 ), thereby causing the lock out (not shown) to move proximally such that a distal face of the lock out moves out of contact with camming member  288 , which causes camming member  288  to cam into recess  249  of distal drive member  248 . In this manner, distal drive member  248  is prevented from distal and/or proximal movement. When lock button  282  is moved from the proximal position to the distal position, the distal end of actuation bar  284  moves distally into the lock out (not shown), against the bias of a biasing member (not shown), to force camming member  288  out of recess  249 , thereby allowing unimpeded axial translation and radial movement of distal drive member  248 . 
     With reference to  FIGS. 32-39 , adapter  200  includes an electrical assembly  290  supported on and in outer knob housing  202  and inner housing assembly  204 . Electrical assembly  290  includes a plurality of electrical contact blades  292 , supported on a circuit board  294 , for electrical connection to pass-through connector  66  of plate assembly  60  of outer shell housing  10  of surgical device  100 . Electrical assembly  290  serves to allow for calibration and communication information (i.e., identifying information, life-cycle information, system information, force information) to the main controller circuit board  142   b  of power-pack core assembly  106  via electrical receptacle  149  of power-pack core assembly  106  of surgical device  100 . Such communication is described in greater detail below with reference to  FIGS. 70-82 . 
     Electrical assembly  290  further includes a strain gauge  296  electrically connected to circuit board  294 . Strain gauge  296  is provided with a notch  296   a  which is configured and adapted to receive stem  204   d  of hub  204   a  of inner housing assembly  204 . Stem  204   d  of hub  204   a  functions to restrict rotational movement of strain gauge  296 . As illustrated in  FIGS. 32, 35 and 39 , first rotatable proximal drive shaft  212  extends through strain gauge  296 . Strain gauge  296  provides a closed-loop feedback to a firing/clamping load exhibited by first rotatable proximal drive shaft  212 , based upon which power-pack core assembly  106  sets the speed current limit on the appropriate motor  152 ,  154 ,  156 . 
     Electrical assembly  290  also includes a slip ring  298  non-rotatably and slidably disposed along drive coupling nut  244  of outer tube  206 . Slip ring  298  is in electrical connection with circuit board  294 . Slip ring  298  functions to permit rotation of first rotatable proximal drive shaft  212  and axial translation of drive coupling nut  244  while still maintaining electrical contact of electrical contact rings  298   a  thereof with at least another electrical component within adapter  200 , and while permitting the other electrical components to rotate about first rotatable proximal drive shaft  212  and drive coupling nut  244 . 
     Electrical assembly  290  may include a slip ring cannula or sleeve  299  positioned about drive coupling nut  244  to protect and/or shield any wires extending from slip ring  298 . 
     Turning now to  FIGS. 26, 33 and 35 , inner housing assembly  204  includes a hub  204   a  having a distally oriented annular wall  204   b  defining a substantially circular outer profile, and defining a substantially tear-drop shaped inner recess or bore  204   c . Bore  204   c  of hub  204   a  is shaped and dimensioned to slidably receive articulation bearing assembly  252  therewithin. 
     Inner housing assembly  204  includes a ring plate  254   a  ( FIG. 26 ) secured to a distal face of distally oriented annular wall  204   b  of hub  204   a . Plate  254   a  defines an aperture  254 e therethrough that is sized and formed therein so as to be aligned with second proximal drive shaft  214  and to rotatably receive a distal tip  214   c  of second proximal drive shaft  214 . In this manner, distal tip  214   c  of second proximal drive shaft  214  is supported and prevented from moving radially away from a longitudinal rotational axis of second proximal drive shaft  214  as second proximal drive shaft  214  is rotated to axially translate articulation bearing assembly  252 . 
     As illustrated in  FIG. 35 , hub  204   a  defines a feature (e.g., a stem or the like)  204   d  projecting therefrom which functions to engage notch  296   a  of strain gauge  296  of electrical assembly  290  to measure forces experienced by shaft  212  as surgical device  100  is operated. 
     With reference to  FIGS. 26 and 38 , a plate bushing  230  of inner housing assembly  204  is shown and described. Plate bushing  230  extends across hub  204   a  of inner housing assembly  204  and is secured to hub  204   a  by fastening members. Plate bushing  230  defines three apertures  230   a ,  230   b ,  230   c  that are aligned with and rotatably receive respective first, second and third proximal drive shafts  212 ,  214 ,  216  therein. Plate bushing  230  provides a surface against which first, second and third biasing members  224 ,  226  and  228  come into contact or rest against. 
     With reference to  FIGS. 48-52 , adapter  200  includes a distal cap  208  extending distally from distal portion  206   b  of outer tube  206 . Adapter  200  further includes a switch  320 , a sensor link or switch actuator  340 , an annular member  360 , and actuation bar  284 , each being disposed within outer tube  206 . Switch  320  is configured to toggle in response to a coupling of SULU  400  to distal portion  206   b  of outer tube  206 . Switch  320  is configured to couple to a memory  432  of SULU  400 . The memory  423  of SULU  400  is configured to store data pertaining to SULU  400  and is configured to provide the data to controller circuit board  142  of surgical device  100  in response to SULU  400  being coupled to distal portion  206   b  of outer tube  206 , as detailed below with reference to  FIGS. 70-82 . Switch  320  is disposed within distal portion  206   b  of outer tube  206  and is oriented in a proximal direction. Switch  320  is mounted on a printed circuit board  322  that is electrically connected with controller circuit board  142  of power-pack  101 . As detailed below, power-pack core assembly  106  monitors the 1-wire communication bus between power-pack core assembly  106  and adapter  200  and is able to detect that SULU  400  is engaged to distal portion  206   b  of outer tube  206  or that SULU  400  is disengaged from distal portion  206   b  of outer tube  206  by recognizing that switch  230  has been toggled. 
     Adapter  200  includes, as illustrated in  FIGS. 48 and 51 , a switch actuator  340  slidingly disposed within distal portion  206   b  of outer tube  206 . Switch actuator  340  is longitudinally movable between a proximal position, as shown in  FIGS. 48 and 51 , and a distal position, as shown in  FIG. 63 . The switch actuator  340  toggles switch  320  during movement between proximal and distal positions. 
     Switch actuator  340  has a proximal end portion  342   a  and a distal end portion  342   b . Proximal end portion  342   a  of switch actuator  340  includes an inner surface  344  that defines an elongated opening  346  having a coil spring  348  disposed therein. Coil spring  348  is secured within opening  346  between a distal end  344   a  of inner surface  344  and a projection  350  of inner housing  314 , which projects through opening  346 . 
     Distal end portion  342   b  of switch actuator  340  includes an extension  352  having a tapered portion  352   a . Extension  352  is engaged to a first surface feature  376   a  of annular member  360  when annular member  360  is in a selected orientation relative to extension  352 , such that switch actuator  340  is maintained in the proximal position. Switch actuator  340  further includes a tab  354  extending from an intermediate portion  356  thereof. Coil spring  348  resiliently biases switch actuator  340  toward the distal position, as shown in  FIGS. 48, 61 and 63 , in which tab  354  actuates or depresses switch  320 . 
     With reference to  FIGS. 48-52 , adapter  200  includes an annular member  360 , which is rotatably disposed within inner housing  314  of outer tube  206 . Annular member  360  extends from a proximal end  362   a  to a distal end  362   b  and defines a cylindrical passageway  364  therethrough configured for disposal of an inner housing  410   b  of SULU  400 , as described in greater detail below. Annular member  360  includes a longitudinal bar  366  defining an elongated slot  368  along a length thereof configured for sliding disposal of a fin  420  of inner housing  410   b  ( FIG. 66-68 ) of SULU  400 . Proximal end  362   a  includes a first ring  370   a  and distal end  362   b  includes a second ring  370   b , spaced from first ring  370   a  along longitudinal bar  366 . First ring  370   a  includes a pair of electrical contacts  372  electrically coupled to switch  320  via wires  374 . Electrical contacts  372  are configured to engage corresponding electrical contacts  430  of SULU  400 , such that switch  320  and annular member  360  are capable of transferring data pertaining to SULU  400  therebetween, ultimately for communication with power-pack core assembly  106 , as described in greater detail below. It is contemplated that a portion of annular member  360  is ring-shaped. 
     With specific reference to  FIGS. 51 and 52 , annular member  360  also includes a first surface feature  376   a , and a second surface feature or tab  376   b , each extending from second ring  370   b . Surface feature  376   a  of annular member  360  is configured to interface with a first surface feature or first lug  412   a  ( FIGS. 61-64 ) of SULU  400 , such that annular member  360  is rotatable by and with SULU  400 . Specifically, surface feature  376   a  defines a cavity  378  therein having a squared configuration configured for mating engagement with correspondingly shaped first lug  412   a  of SULU  400 . Cavity  378  is shaped and dimensioned to capture first lug  412   a  ( FIGS. 57 and 58 ) of SULU  400  upon insertion of SULU  400  into adapter  200 , such that annular member  360  is rotatable with and by SULU  400 . Surface feature  376   a  of annular member  360  is also configured to abut extension  352  of switch actuator  340  to maintain switch actuator  340  in the proximal position. 
     Annular member  360  is rotatable between a first orientation and a second orientation. In the first orientation, as shown in  FIGS. 51 and 52 , surface feature  376   a  of annular member  360  is captured between a proximal lip  208   a  of distal cap  208  and extension  352  of switch actuator  340 . In this configuration, the surface feature  376   a  prevents distal movement of switch actuator  340  from the proximal position to the distal position, thereby maintaining tab  354  of switch actuator  340  out of engagement with switch  320 . Accordingly, surface feature  376   a  of annular member  360  has a dual function for both maintaining switch actuator  340  in the proximal position, out of engagement with switch  320 , and capturing first lug  412   a  of SULU  400  in cavity  378  to provide an interface between SULU  400  and annular member  360 . 
     In use, SULU  400  is inserted within the distal end of outer tube  206  of adapter  200  to mate first lug  412   a  of SULU  400  with first surface feature  376   a  of annular member  360 , as shown in  FIG. 61 . SULU  400  is rotated, in a direction indicated by arrow “C” ( FIG. 63 ), to drive a rotation of annular member  360  from the first orientation to the second orientation. Rotation of annular member  360  from the first orientation to the second orientation disengages surface feature  376   a  of annular member  360  from extension  352  of switch actuator  340  such that coil spring  348  of switch actuator  340  biases switch actuator  340  toward the distal position, in which switch  320  is toggled, as shown in  FIG. 63 . 
     With continued reference to  FIG. 52 , annular member  360  further includes a projection or tab  376   b  extending from second ring  370   b . Tab  376   b  has a planar configuration and is configured to resist and/or prevent inadvertent rotation of annular member  360  within inner housing  314  when SULU  400  is not engaged to adapter  200 . With specific reference to  FIG. 52 , when annular member  360  is in the first orientation, tab  376   b  is secured between a projection  208   b  of distal cap  208  and a distal end  284   a  of actuation bar  284 . Rotation of annular member  360  from the first orientation to the second orientation is resisted and/or prevented until actuation bar  284  is moved to a second configuration, as described below. In this way, tab  376   b  ensures that first surface feature  376   a  of annular member  360  is maintained in abutment with extension  352  of switch actuator  340  thereby maintaining switch actuator  340  in the proximal position until SULU  400  is engaged to adapter  200 . 
     With reference to  FIGS. 36, 52, 62 and 64 , and as discussed briefly above, adapter  200  further includes a lock mechanism  280  having a button  282  slidably supported on outer knob housing  202 , and an actuation bar  284  extending from button  282 . Actuation bar  284  extends longitudinally through outer tube  206 . Specifically, actuation bar  284  is slidingly disposed within or along inner housing  314  of adapter  200  and is resiliently biased toward a first configuration, as shown in  FIG. 64 . In the first configuration, a distal end or extension  284   a  of actuation bar  284  is engaged with distal cap  208 . Extension  284   a  of actuation bar  284  is configured for engagement with a second lug  412   b  ( FIG. 64 ) of SULU  400  upon insertion and rotation of SULU  400  into adapter  200 . As shown in  FIG. 62 , SULU  400  engages adapter  200  and actuation bar  284  in the first configuration, second lug  412   b  of SULU  400  is captured in an enclosure  286  defined by extension  284   a  of actuation bar  284  and distal cap  208 . 
     As illustrated in  FIGS. 1 and 54-56 , SULU is designated as  400 . SULU  400  includes a proximal body portion  402  and a tool assembly  404 . Proximal body portion  402  is releasably attached to a distal cap  208  of adapter  200  and tool assembly  404  is pivotally attached to a distal end of proximal body portion  402 . Tool assembly  404  includes an anvil assembly  406  and a cartridge assembly  408 . Cartridge assembly  408  is pivotal in relation to anvil assembly  406  and is movable between an open or unclamped position and a closed or clamped position for insertion through a cannula of a trocar. Proximal body portion  402  includes at least a drive assembly  460  and an articulation link  466 . 
     Referring to  FIG. 54 , drive assembly  460  includes a flexible drive beam  464  having a distal end and a proximal engagement section. A proximal end of the engagement section includes diametrically opposed inwardly extending fingers that engage a hollow drive member  474  to fixedly secure drive member  474  to the proximal end of beam  464 . Drive member  474  defines a proximal porthole which receives connection member  247  of drive tube  246  of first drive converter assembly  240  of adapter  200  when SULU  400  is attached to distal cap  208  of adapter  200 . 
     Proximal body portion  402  of SULU  400  includes an articulation link  466  having a hooked proximal end which extends from a proximal end of SULU  400 . 
     As illustrated in  FIG. 54 , cartridge assembly  408  of tool assembly  404  includes a staple cartridge removably supported in a carrier. The staple cartridge defines a central longitudinal slot, and three linear rows of staple retention slots positioned on each side of the longitudinal slot. Each of the staple retention slots receives a single staple and a portion of a staple pusher. During operation of surgical device  100 , drive assembly  460  abuts an actuation sled and pushes actuation sled through the cartridge. As the actuation sled moves through the cartridge, cam wedges of the actuation sled sequentially engage the staple pushers to move the staple pushers vertically within the staple retention slots and sequentially ejects a single staple therefrom for formation against an anvil plate of anvil assembly  406 . 
     To fully disengage SULU  400  from adapter  200 , SULU  400  is axially translated, in a distal direction, through distal cap  208 , and out of outer tube  206  of adapter  200 . It is contemplated that upon surgical device  100  detecting that SULU  400  is not engaged to adapter  200 , power may be cut off from adapter  200 , and alarm (e.g., audio and/or visual indication) may be issued, and combinations thereof, as detailed below. 
     With reference to  FIGS. 54-60 , SULU  400  further includes an outer housing  410   a  and an inner housing  410   b  disposed within outer housing  410   b . First and second lugs  412   a ,  412   b  are each disposed on an outer surface of a proximal end  414  of outer housing  410   a . First lug  412   a  has a substantially rectangular cross-section corresponding to cavity  378  of surface feature  376   a  of annular member  360  of adapter  200 . Second lug  412   b  has a substantially rectangular cross-section corresponding to inner groove  208   c  of distal cap  208  of adapter  200 . Proximal end  414  of outer housing  410   a  is sized and dimensioned to be inserted through distal cap  208  to engage adapter  200 . 
     Outer housing  410   a  defines a first notch  416   a  and a second notch  416   b  in a proximal-most edge thereof. First notch  416   a  is configured for sliding receipt of a tapered fin  420  extending from inner housing  410   b . At least a portion of fin  420  is configured for disposal in slot  468  defined in longitudinal bar  366  of annular member  360  to facilitate insertion of inner housing  410   b  into annular member  360 . Second notch  416   b  is configured for a snap fit engagement with a pair of parallel, resilient fingers  422  of inner housing  410   b . Second notch  416   b  generally has a rectangular configuration with a pair of grooves  418  defined therein. Each finger  422  has a mating part  424  configured for mating engagement with one respective groove  418  of second notch  416   b . Outer housing  410   a  further defines a pair of channels  426  defined in an interior surface  428  thereof and disposed on either side of first notch  416   a . Each channel  426  of outer housing  410   a  is configured for disposal of a portion of an electrical contact  430  of inner housing  410   b , as described in greater detail below. 
     In use, fin  420  and fingers  422  of inner housing  410   b  are aligned with first and second notches  416   a ,  416   b  of outer housing  410   a , respectively, and inner housing  410   b  is axially translated within outer housing  410   a , until mating parts  424  of fingers  422  are captured in grooves  418  of second notch  416   b  to capture inner housing  410   b  within outer housing  410   a.    
     SULU  400  further includes a memory  432  disposed within or on inner housing  410   b . Memory  432  includes a memory chip  434  and a pair of electrical contacts  430  electrically connected to memory chip  434 . Memory chip  434  is configured to store one or more parameters relating to SULU  400 . The parameter includes a serial number of a loading unit, a type of loading unit, a size of loading unit, a staple size, information identifying whether the loading unit has been fired, a length of a loading unit, maximum number of uses of a loading unit, and combinations thereof. Memory chip  434  is configured to communicate to surgical device  100  a presence of SULU  400  and one or more of the parameters of SULU  400  via electrical contacts  430 , upon engagement of SULU  400  with adapter  200 , as detailed below. 
     Electrical contacts  430  are disposed on an outer surface of inner housing  410   b  and are configured to engage electrical contacts  372  of annular member  360  upon insertion of SULU  400  into adapter  200 . A proximal end of each electrical contact  430  has a bent portion  436  extending beyond a proximal-most edge of outer housing  410   a  of SULU  400  when inner housing  410   b  is secured within outer housing  410   a , as shown in  FIGS. 57 and 58 . Bent portions  436  of electrical contacts  430  of SULU  400  engage electrical contacts  372  of annular member  360  upon insertion of SULU  400  within annular member  360  of adapter  200 . This connection between the contacts  372  and  430  allows for communication between memory chip  434  of SULU  400  and controller circuit board  142  of surgical device  100 . In particular, controller circuit board  142  of surgical device  100  receives one or more parameters pertaining to SULU  400  and that SULU  400  is engaged to adapter  200 . 
     In operation, SULU  400  is inserted into distal end  206   b  of outer tube  206  of adapter  200  to matingly engage first lug  412   a  of SULU  400  within cavity  378  of surface feature  376   a  of annular member  360 , as shown in  FIGS. 61-65 . The insertion of SULU  400  within adapter  200  also engages second lug  412   b  with extension  284   a  of actuation bar  284  to move actuation bar  284  in a proximal direction, as shown in the direction indicated by arrow “B” in  FIG. 62 , to the second configuration, and out of abutment with tab  376   b  of annular member  360 . In this way, extension  284   a  of actuation bar  284  no longer prevents annular member  360  from rotating. With SULU  400  in this initial insertion position within adapter  200 , switch actuator  340  remains in the proximal position out of engagement with switch  320 . 
     To engage SULU  400  with adapter  200 , SULU  400  is rotated, in a direction indicated by arrow “C” in  FIG. 63 , to drive a rotation of annular member  360 , via the mating engagement between first lug  412   a  of SULU  400  and surface feature  376   a  of annular member  360 , from the first orientation to the second orientation. The rotation of annular member  360  from the first orientation to the second orientation displaces surface feature  376   a  of annular member  360  away from extension  352  of switch actuator  340 . With surface feature  376   a  out of engagement with extension  352  of switch actuator  340 , switch actuator  340  moves from the proximal position, as shown in  FIGS. 48 and 51 , to the distal position, as shown in  FIG. 63 , via coil spring  348 . As switch actuator  340  moves to the distal position, tab  354  of switch actuator  340  toggles switch  320 , e.g., by depressing switch  320 , as shown in  FIG. 63 . Depressing or actuating switch  320  communicates to surgical device  100  that SULU  400  is engaged with adapter  200  and is ready for operation. 
     The rotation of SULU  400  also moves second lug  412   b  of SULU  400  into an inner groove  208   c  defined in distal cap  208  of adapter  200  and out of engagement with extension  284   a  of actuation bar  284 . The resilient bias of actuation bar  284  drives an axial translation of actuation bar  284 , in a direction indicated by arrow “D” in  FIG. 64 , to dispose actuation bar  284  into the first configuration. With actuation bar  284  in the first configuration, second lug  412   b  of SULU  400  is captured within enclosure  286  defined by extension  284   a  of actuation bar  284  and inner groove  208   c  of distal cap  208  of adapter  200 . SULU  400  is prevented from moving distally out of enclosure  286  due to an inner ledge  208   d  of inner groove  208   c  of distal cap  208  of adapter  200 , and is prevented from rotating, in a direction indicated by arrow “E” shown in  FIG. 64 , due to extension  284   a  of actuation bar  284 . Therefore, SULU  400  is releasably, engaged to adapter  200 . 
     To selectively release SULU  400  from adapter  200 , a practitioner translates or pulls actuation bar  284  in a proximal direction, such that extension  284   a  of actuation bar  284  is no longer blocking second lug  412   b  of SULU  400  and SULU  400  can be rotated. SULU  400  is rotated, in a direction indicated by arrow “F” in  FIG. 63 , to move second lug  412   b  of SULU  400  out of abutment with inner ledge  208   d  of distal cap  208 . The rotation of SULU  400  also drives the rotation of annular member  360  from the second orientation to the first orientation via the mating engagement of first lug  412   a  of SULU  400  and surface feature  376   a  of annular member  360 . As annular member  360  rotates, surface feature  376   a  rides along tapered portion  352   a  of extension  352  of switch actuator  340  to drive switch actuator  340  in a proximal direction until annular member  360  is in the first orientation and switch actuator  340  is in the proximal position, out of engagement with switch  320 . Upon tab  354  of switch actuator  340  disengaging switch  320 , switch  320  is toggled, which communicates to surgical device  100  that SULU  400  may be pulled out of adapter  200 . 
     In operation, SULU  400 , with inner housing  410   b  disposed within outer housing  410   a , is manipulated to align fin  420  of inner housing  410   b  and electrical contacts  430  of inner housing  410   b  with longitudinal bar  366  of annular member  360  and electrical contacts  372  of annular member  360 , respectively. SULU  400  is inserted within the distal end of adapter  200  thereby engaging first lug  412   a  of outer housing  410   a  within surface feature  376   a  of annular member  360  and forming a wiping contact between electrical contacts  430  of inner housing  410   b  and electrical contacts  372  of annular member  360 , as shown in  FIGS. 63 and 64 . 
     As described above with reference to  FIGS. 61 and 62 , upon the initial insertion of SULU  400  into adapter  200 , switch actuator  340  remains disengaged from switch  320 . With switch  320  in the unactuated state, there is no electrical connection established between memory chip  434  of SULU  400  and controller circuit board  142  of surgical device  100 . As discussed above, upon a rotation of SULU  400 , SULU  400  engages adapter  200  and switch actuator  340  toggles switch  320  to actuate switch  320 . With switch  320  in the actuated state, an electrical connection is established between memory chip  434  and controller circuit board  142  of surgical device  100 , through which information about SULU  400  is communicated to controller circuit board  142  of surgical device  100 . Upon both the actuation of switch  320  and the establishment of a wiping contact between electrical contacts  430  of inner housing  410   b  and electrical contacts  372  of annular member  360 , surgical device  100  is able to detect that SULU  400  has been engaged to adapter  200  and to identify one or more parameters of SULU  400 . 
     Referring to  FIGS. 53 and 69A-69D , SULU  400 , as detailed above, is a single-use, EGIA-type loading unit. However, as noted above, other types of loading units are also capable of being used with surgical device  100  including EEA loading unit  900 A, MULU  900 B, transverse loading unit  900 C, and curved loading unit  900 D. As detailed below, the particular loading unit utilized is recognized by power-pack core assembly  106  to enable appropriate operation thereof. 
     With reference to  FIG. 69A , EEA loading unit  900 A includes a proximal body portion  902 A and tool assembly  904 A for circular stapling and cutting, e.g., during the course of an end-to-end anastomosis procedure. Similar to SULU  400  ( FIG. 53 ), EEA loading unit  900 A includes an internal memory chip that includes a memory configured to store data pertaining to loading unit  900 A. Generally, loading unit  900 A is operated when attached to adapter  200  ( FIG. 20 ) in a similar manner as described above with regard to SULU  400  ( FIG. 53 ). 
     With reference to FIG.  69 B 1  and  69 B 2 , MULU  900 B is similar to SULU  400  ( FIG. 53 ) and includes a proximal body portion (not shown) and a tool assembly having an anvil assembly  906 B and a cartridge assembly  908 B. However, MULU  900 B differs from SULU  400  ( FIG. 53 ) mainly in that cartridge assembly  908 B is configured to removably receive a staple cartridge  910 B that, after use, is replaced with a replacement staple cartridge  910 B for subsequent use of MULU  900 B. Alternatively, MULU  900 B may contain multiple staple cartridges disposed therein to enable repeated use without requiring replacement of staple cartridge  910 B. Similar to SULU  400  ( FIG. 53 ), MULU  900 B includes an internal memory chip that includes a memory configured to store data pertaining to MULU  900 B. Generally, MULU  900 B is operated when attached to adapter  200  ( FIG. 20 ) in a similar manner as described above with regard to SULU  400  ( FIG. 53 ). 
     Transverse loading unit  900 C and curved loading unit  900 D, as illustrated in  FIGS. 69C and 69D , respectively, are still further configurations of loading units configured for use with surgical device  100 . Similar to SULU  400  ( FIG. 53 ) and the other embodiments of loading units detailed herein, transverse loading unit  900 C and curved loading unit  900 D each include an internal memory chip having a memory configured to store data pertaining to the respective loading unit  900 C,  900 D and are generally operated when attached to adapter  200  ( FIG. 20 ) in a similar manner as described above. 
     Turning now to  FIGS. 70-82  the communication, safety, and control features of surgical device  100  are described. As noted above, controller circuit board  142  of power-pack core assembly  106  includes motor controller circuit board  142   a  and main controller circuit board  142   b . Controller circuit board  142  is coupled to battery circuit board  140  and a switch board  177  of switch assembly  170  ( FIG. 15 ). 
     Main controller circuit board  142   b  includes master chip  157  and supports memory  165 , which in an embodiment, is a micro SD memory. Main controller circuit board  142   b  further includes a 1-wire communication system including three 1-wire buses. A 1-wire master chip  166  of main controller circuit board  142   b  controls communications across three 1-wire buses  167 ,  169 ,  171 . Although described herein as a 1-wire communication system, it is contemplated that other suitable communication systems for enabling the functionality detailed herein may also be provided. 
     First 1-wire bus  167  establishes a communication line between master chip  157  and motor controller circuit board  142   a , which connects to battery circuit board  140  of battery  144  when battery  144  is present, thereby establishing a communication line between power-pack core assembly  106  and battery  144 . 
     Second 1-wire bus  169  establishes a communication line between master chip  157  and a switchboard/adapter intermediate  175 , which includes electrical adapter interface receptacle  149 , and is configured to connect to a 1-wire memory chip of circuit board  294  of adapter  200  when adapter  200  is present. Switchboard/adapter intermediate  175  also couples switch board  177  with main controller board  142   b  via a third ribbon cable  142 e. Second 1-wire bus  169  establishes a communication line between power-pack core assembly  106  and adapter  200  and also enables information stored in the 1-wire memory chip of circuit board  294  of adapter  200  to be accessed, updated, and/or incremented by power-pack core assembly  106 . Circuit board  294  of adapter  200 , in addition to having the 1-wire chip, includes a memory and electrical contacts  292  that enable electrical connection to the power-pack core assembly  106  to allow for calibration and communication of data and control signals therebetween. The memory is configured to store data relating to adapter  200  such as unique ID information (electronic serial number); type information; status information; whether a loading unit has been detected, identified, and verified; usage count data; and assumed autoclave count data. Distal electrical contacts  272  of adapter  200 , as noted above, are configured to electrically couple with the corresponding electrical contacts  330  of a loading unit engaged therewith, e.g., SULU  400 , for communication therewith, while toggle switch  230  permits the power-pack core assembly  106  to detect the presence of SULU  400 . The memory of the SULU  400  stores data relating to SULU  400  such as a serial number, the type of the loading unit, the size of the loading unit, the staple size, the length of the loading unit, and an indication of whether the loading unit has been fired. Power-pack core assembly  106  is capable of reading this information stored in the memory of SULU  400  via adapter  200 . 
     Third 1-wire bus  171  enables communication between master chip  157  in power-pack core assembly  106  and the 1-wire memory chip of outer shell housing  10 . As detailed above, the 1-wire chip in outer shell housing  10  includes a memory that stores a unique ID of outer shell housing  10  and is capable of being updated to mark outer shell housing  10  as “used.” Electrical contacts associated with the outer shell housing  10  form part of third 1-wire bus  171  and enable communication between power-pack core assembly  106  and 1-wire chip of the outer shell housing  10 . 
     Power-pack core assembly  106  further includes and/or is coupled to various hardware components (some of which have been detailed above) that facilitate the various functions of power-pack core assembly  106  including: a Wifi board  182 , the display screen  146 , an accelerometer  184 , the universal serial bus (USB) port  180 , an infrared detection module  186 , a real-time clock (RTC), an expansion port  188 , and the FPGA  162 , which as mentioned above enables communication between main controller  157  and motor controllers “MC 0 ,” MC 1 ,” “MC 2 ” of motor controller circuit board  142   a . Wifi board  182  and/or USB port  180  are used for communicating data collected by power-pack core assembly  106 , adapter  200 , and/or loading unit  300  to an external communication system. Accelerometer  184  enables determination of whether power-pack core assembly  106  has been manipulated, rotated, moved, etc. The RTC provides a reference from which the various time and/or duration-dependent functionality may be established. 
       FIG. 71  is a block diagram of a simplified system architecture  1100  for controlling components of surgical device  100  ( FIG. 1 ). Architecture  1100  includes a processor  1102  in operable communication with a memory  1104 , which has various modules that include instructions for surgical device  1000  to operate in a desired manner, based on received user input or detected data. Processor  1102  is included on one or more of the boards of controller circuit board  142  ( FIG. 70 ) and is made up of one or more devices. Here, for example, master chip  157 , motor controllers “MC 0 ,” “MC 1 ,” “MC 2 ,” 1-wire master chip  166 , and other controllers make up processor  1102  (see  FIG. 70 ). Memory  1104  is computer-readable media and resides in one or more locations, such as, for example, memory  165  of main controller circuit board  142  and the 1-wire memory chips of adapter  200  and outer shell housing  10  (see  FIGS. 1 and 70 ). In an embodiment, memory  1104  may include one or more solid-state storage devices such as flash memory chips. Alternatively or in addition to the one or more solid-state storage devices, memory  1104  may include one or more mass storage devices connected to the processor  1102  through a mass storage controller (not shown) and a communications bus (not shown). Although the description of computer-readable media contained herein refers to a solid-state storage, it should be appreciated by those skilled in the art that computer-readable storage media can be any available media that can be accessed by the processor  1102 . That is, computer readable storage media includes non-transitory, volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. For example, computer-readable storage media includes RAM, ROM, EPROM, EEPROM, flash memory or other solid state memory technology, CD-ROM, DVD, Blu-Ray or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by processor  1102 . 
     Memory  1104  includes an application  1106 , which stores instructions for the operation of surgical device  100  ( FIG. 1 ), and a database  1108 , which stores collected data relating to surgical device  100  ( FIG. 1 ). Application  1106  includes a mode module  1112 , an initialization module  1114 , a charging module  1116 , a validation module  1118 , a calibration module  1120 , and an operation module  1122 . Each of these modules will be described in greater detail below. 
     Mode module  1112  instructs a power-pack (e.g., power-pack core assembly  106  ( FIG. 13 )) to enter or exit operational modes and enters/exits these modes depending upon its condition, last use, motion, whether any components are attached, and/or whether it is connected to a charger. Specifically, the power-pack is transitionable from a ship mode and, thereafter, between a standby mode, a sleep mode, and an active mode.  FIG. 72  is a diagram of a method  1200  depicting a flow by which the power-pack enters/exits the various modes thereof. Initially, the power-pack is in the ship mode at S 1202 . When the power-pack enters initial startup at S 1204 , it undergoes an initialization wherein the ship mode is permanently exited at S 1206 . It is contemplated that the battery of the power-pack be provided in an un-charged state and, as such, initialization begins upon connection of the power-pack with the charger. Until such initialization, the power-pack remains in ship mode at S 1202 . Once the ship mode has been exited, the power-pack is transitional between the standby mode, the sleep mode, and the active mode, and enables and/or disables certain functionality based upon its mode. 
     Entry into one of the various modes depends on whether the power-pack includes a clamshell, e.g., outer shell housing  10 , engaged thereabout. Accordingly, with continued reference to  FIG. 72 , a determination is made as to whether the outer shell housing is attached to the power-pack at S 1208 . With respect to surgical device  100 , this determination is made by the master chip  157  scanning third 1-wire bus  171  in search of a 1-wire memory chip of outer shell housing  10  (see  FIGS. 1 and 70 ). When no outer shell housing is attached, an “insert clamshell” screen is displayed on a display screen to communicate to the user that no outer shell housing is attached to the power-pack. While the outer shell housing is not attached to the power-pack, button presses do not elicit motor responses. For example, open, close, safety and articulate buttons do not function. However, the power-pack is able to connect to an external communication system, and a screen depicting connection to the external communication system is displayed on the display screen. If a rotate button is pressed, a current power-pack statistics screen is displayed for a desired duration, for example, five (5) seconds. 
     Next, a determination is made as to whether the power-pack has been used at S 1210 . Usage includes, for example, placing the power-pack on the charger for recharging the battery, e.g., battery  144  ( FIG. 70 ), pressing any of the various buttons on the power-pack, attaching an outer shell housing to the power-pack, or manipulating the power-pack (as determined by the accelerometer). When the power-pack has been idle for a time period that is greater than a first predetermined threshold duration, e.g., thirty (30) seconds of no usage, the power-pack enters standby mode at S 1212 . Otherwise, the power-pack enters an active mode at S 1214 . As indicted by S 1230 , if entry into the active mode at S 1214  is triggered via connection of an outer shell housing to the power-pack, the active mode at S 1220 , which is detailed below, is achieved. 
     At S 1216 , while in standby mode, another determination is made as to whether the power-pack is being used. Here, a determination is made as to whether the power-pack has been idle for a time period that is greater than a second predetermined threshold duration, where the second predetermined threshold duration of step S 1216  is greater than the first predetermined threshold duration of step S 1210 , for example, in a range of five (5) to twenty (20) minutes, e.g., fifteen (15) minutes. If at S 1216  the power-pack does not remain idle for a time period that is greater than the predetermined threshold duration, the power-pack enters an active mode at S 1214 . If the power-pack does remain idle for a time period that is greater than the predetermined threshold duration, the power-pack exits the standby mode and enters a sleep mode at S 1218 . Method  1200  then proceeds to S 1216  to determine whether to exit sleep mode and enter active mode at S 1214  or remain in sleep mode at S 1218 . 
     Returning to S 1208 , when an outer shell housing is attached to the power-pack, the active mode is entered at S 1220  so that the power-pack is ready for use. For instance, the power-pack monitors 1-wire bus  171  ( FIG. 70 ) at a minimum rate of 1 Hz for the presence of attachment of an outer shell housing  10  ( FIG. 1 ). A determination then is made at S 1222  as to whether the power-pack is in use. Usage includes, for example, motion of the power-pack, pressing any of the various buttons, detection of another outer shell housing (e.g., if the outer shell housing is removed and replaced with another outer shell housing), or attachment of an adapter. When the power-pack is in use, the power-pack remains in the active mode and returns to S 1220 . When the power-pack is not in use after a predetermined threshold duration, for example, after one (1) minute of non-usage, the power-pack enters the standby mode at S 1224 . During the standby mode, the power-pack returns to S 1222  continuing to monitor whether usage occurs. In an embodiment, if the outer shell housing is a demonstration component, motion does not cause the power-pack to exit the standby mode. If an adapter, e.g., adapter  200 , is already attached to the power-pack, attachment of a loading unit, e.g., SULU  400  ( FIG. 1 ), loading unit  900 A ( FIG. 69A ), MULU  900 B (FIGS.  69 B 1  and  69 B 2 ), loading unit  900 C ( FIG. 69C ), or loading unit  900 D ( FIG. 69D ), to the adapter will also cause the power-pack to exit the standby mode and to enter the active mode at S 1220 . Multi-use loading units, e.g., MULU  900 B (FIGS.  69 B 1  and  69 B 2 ), include replaceable staple cartridges, and hence, may be referred to as a reload. For purposes of consistency in describing the methods performed by application  1106 , loading units and reloads for use with multi-use loading units will be referred to below simply as “reloads.” 
     Initialization module  1114  controls initialization of the power-pack. In particular, initialization module  1114  includes instructions for the power-pack to perform a plurality of self-tests at initialization, which occurs when the power-pack exits the ship mode, the power-pack is removed from the charger, the power-pack is woken up from sleep mode, or when initiated by the user. The initialization self-tests include a test of the display screen, a test of the memory of the power-pack, an RTC test, an FPGA communication test, a test of the motor and drive electronics, a test of the accelerometer, a button active test, a plurality of 1-wire tests, and a use-remaining test. 
     Turning now to  FIG. 73 , a flow diagram is provided depicting a method  1300  for initializing the power-pack. Initialization begins at S 1302  when the power-pack exits the ship mode, the power-pack is removed from the charger, the power-pack is woken up from the sleep mode, or when initiated by the user. Although any one of the initialization tests can be initially performed, for the purposes of this description, the display screen is initially tested at S 1304 . The display test includes verifying communication capability between the power-pack and the display controller, turning on all pixels to the color white for 500 milliseconds (mS), and, upon completion, displaying the “welcome” screen on the display screen. Next, a determination is made at S 1306  as to whether any of the initialization tests have not yet been performed. If so, a next test to be performed is identified at S 1308 . If not, method  1300  ends. 
     If identified as being next to be performed, the clock is verified at S 1310 . In an embodiment, testing is performed to determine whether the clock is functional. Next, S 1306  is performed, and S 1308 , if needed, is performed to identify a next test. 
     If identified as being the next test to be performed, the memory of the power-pack is verified at S 1312 . For example, verification includes one or more of verifying the integrity of the code stored in the program memory of the power-pack, the integrity of the external SRAM, the ability to communicate with the SD memory, e.g., memory  165  ( FIG. 70 ), and the integrity of the file system on the SD card. In an embodiment, if the integrity of the code is not verified, method  1400  is performed as shown in  FIG. 74 . In particular, if verification of the code fails, no further operation is possible at S 1402  and method  1400  ends. If the verification operation fails, method  1400  at S 1402  is performed (i.e., no further operation is possible) and a fault tone occurs at S 1404 . If verification of the ability to communicate with the SD memory fails, method  1400  at S 1402  is performed (i.e., no further operation is possible) and a fault tone occurs at S 1404 . The fault tone is a single tone or a series of tones within a frequency range. For example, the fault tone is a pattern of tones including a tone within a frequency range of 500 Hertz (Hz)±50 Hz with a duration of 225 mS followed by a tone within a frequency range of 250 Hertz (Hz)±25 Hz with a duration of 225 mS and so on. If the integrity of the file system on the SD card is not verified, the fault tone also occurs at S 1404 . After the memory is tested, method  1300  advances to S 1306 , where a determination is made as to whether any more of the initialization tests remain to be performed, and, if needed, identifying a next test to be performed at S 1308 . 
     In an event in which communication verification is identified as the next test to be performed, step S 1314  is performed. In particular, an FPGA communication test is performed to verify that the FPGA is operational. If the FPGA communication test fails, S 1402  (no further operation is possible), and S 1406  (where an error screen is displayed on the display) are performed. Method  1300  advances to S 1306  and S 1308 , if needed, to identify a next test to be performed. 
     If not yet already performed, a determination is made as to whether an adapter is attached at S 1316 , and if not, a test of the motor and drive electronics is performed to verify the motors of the power-pack at S 1318 . In an event in which any of the motors are unable to attain a commanded position, no further operation is possible as indicated in S 1402 . If one or more of the motors fail, a fault tone occurs as S 1404 , and an error screen is displayed at S 1408 . 
     If at S 1316 , the adapter is identified as being attached or the electronics are verified, method  1300  advances to S 1306  and, if needed, to S 1308  to identify a next test to be performed. If an accelerometer check has not yet been performed, method  1300  advances to S 1320 , during which verification is made as to whether the accelerometer of the power-pack is functional. If the accelerometer is not functional, method  1300  advances to method  1500  of  FIG. 75 . In particular, all operations including firing are possible at S 1501 , a fault tone occurs (S 1504 ), and an error screen is displayed on the power-pack (S 1506 ). If the accelerometer is functional, method  1300  advances to S 1306  and, if needed, to S 1308  which, as noted above, is performed to identify a next test to be performed. 
     If identified as the next test to be performed, wireless functionalities are verified at S 1322 . If the wireless functionalities are verified, method  1300  advances to S 1306 , and if needed, to S 1308  to identify a next test to be performed. If the wireless functionalities are not verified, all operations including firing are possible (S 1501 ), a fault tone occurs (S 1504 ) and an error screen is displayed on the power-pack (S 1506 ). 
     Verification is made with regard to whether a button is active at S 1324 , if not already performed. In the event that the button is active during initialization method  1300 , user operations are ignored until the button is deactivated. Method  1300  then advances to S 1306 , where a determination is made as to whether any other initialization test has not been performed. If so, a next test to be performed is identified at S 1308 . If not, method  1300  ends. 
     If identified as a next test to be performed, the operability of the battery is verified at S 1326 . In an embodiment, numerous tests are performed on the battery. A method  1600  for testing the battery is provided in  FIG. 76 . The battery is initialized by disabling a broadcasting capability of the battery to prevent unsolicited messages from being sent. In the event that communication with the battery fails at  1602 , the method  1600  advances to  FIG. 75 , where all operations except firing are possible ( 1502 ), a fault tone occurs ( 1504 ), and an error screen is displayed on the power-pack ( 1506 ). 
     If communication does not fail, method  1600  proceeds to perform one of the battery tests. Although any of the tests can be initially performed, for the purposes of this description, method  1600  performs the battery capacity (C Batt ) test at S 1608 . The battery capacity may be displayed on the display. In an embodiment, battery capacity testing is performed by determining whether the battery capacity is above a threshold value (e.g., z&lt;C Batt ) at S 1610 . If the battery capacity is not above the threshold value, a determination is made as to whether the battery capacity is within a first range (e.g., y&lt;C Batt &lt;z), where the threshold value is an upper limit of the first range at S 1612 . If so, a tone occurs and a “low battery” error screen is displayed at S 1614 . In an embodiment, the tone is one that is distinguishable from the fault tone and that indicates a low battery. For example, a sequence indicating a low battery occurrence may include a tone at a frequency of 1000 Hz for 50 mS, followed by no tone, followed by a tone at a frequency of 800 Hz for 50 mS, followed by no tone, followed by a tone at a frequency of 600 Hz, followed by no tone, followed by a tone at a frequency of 400 Hz, followed by no tone. 
     If the battery capacity is not within the first range, a determination is made at S 1616  as to whether the battery capacity is within a second range (e.g., x&lt;C Batt &lt;y), where an upper limit of the second range is equal to or below a lower limit of the first range. If the battery capacity is within a second range, a tone indicating an insufficient battery occurs and an “insufficient battery” error screen is displayed at S 1618 . The tone indicating an insufficient battery differs from the tone indicating a low battery. In an embodiment, the low battery tone is a series of tones each at a frequency of 400 Hz±40 Hz in a pattern of on for 50 mS, then off for 50 mS repeated twelve (12) times, and ending with the tone being played for 750 mS. 
     If the battery capacity is not within the second range and thus, is below a lower limit of the second range (e.g., C Batt &lt;x), then a tone indicating a dead battery occurs and a “dead battery” error screen is displayed at S 1620 . The tone indicating a dead battery differs than the tones indicating an insufficient battery or a low battery. In an embodiment, a dead battery is indicated by a series of tones each at a frequency of 400 Hz±40 Hz in a pattern of on for 100 mS, then off for 50 mS, where the pattern is repeated twelve (12) times, and a last tone in the series is played for 750 mS. 
     Referring again to S 1610 , if the battery capacity is above the threshold value (z), method  1600  proceeds to S 1604 , where a determination is made as to whether any of the battery tests have not yet been performed. If so, a next battery test to be performed is identified at S 1606 . If not, method  1600  ends. 
     If not yet already performed, the battery temperature is tested at S 1622 . A determination is made as to whether the battery temperature is in a desired range at S 1624 . In an example, the desired range is 15 to 70 degrees Celsius (° C.). In another embodiment, the desired range is wider than or overlaps the aforementioned range. In yet another embodiment, the desired range is above or below the aforementioned range. If the battery temperature is not within the desired range, either exceeding or falling below the range, a fault tone occurs at S 1626 . If the battery temperature is within the desired range, method  1600  returns to S 1604  and S 1608  to identify a next test to be performed, if any. 
     If not already performed, a battery end-of-life test is performed at  1628  to test a battery full charge capacity for end-of-life condition. In this regard, a determination is made as to whether the battery full charge capacity is less than or equal to a predetermined percentage of design capacity at S 1630 . In an example, the predetermined percentage is about 82%. If the battery full charge capacity is less than or equal to the predetermined percentage, the power-pack is operable except for entering a firing state at S 1632 . If the battery full charge capacity is greater than the predetermined percentage, the test fails and fault tone occurs along with a display of the error on the error screen at S 1634 . A battery charge cycle count is also tested. In particular, a determination is made as to whether the battery charge cycle count is equal to or over a predetermined number of charge cycles at S 1636 . In an embodiment, the predetermined number of charge cycles is three hundred (300) charge cycles. If the battery charge cycle count is equal to or over the predetermined number of charge cycles, the power-pack core assembly  106  can be operated except for entering a firing state, a fault tone occurs, and an error screen is shown on the display at S 1638 . Otherwise, method  1600  advances to S 1604 , and to S 1606 , if needed. 
     Returning to  FIG. 73 , after the battery testing, method  1300  proceeds to S 1306 , to determine whether any of the initialization tests have not yet been performed. If so, a next test to be performed is identified at S 1308 . If not, method  1300  ends. 
     In an instance in which wire testing has not yet been performed, a plurality of wire tests are performed at S 1328  to verify communication capability between the master chip of the power-pack and the various components of the system along the 1-wire bus system. The tests are also employed to verify and record identifying information of the various components. More specifically, tests on all three buses—one between the power-pack and battery, another between the power-pack and outer shell housing, and another between the power-pack and adapter—are performed, followed by verification and identification along the three buses individually. The power-pack monitors the 1-wire buses at a minimum rate of 1 Hz for the presence of an attached outer shell housing, adapter, and/or reload. 
     Turning to  FIG. 77 , a method  1700  for testing the wires is depicted. Although any one of the wire tests can be initially performed, for the purposes of this description, method  1700  begins with a power-pack and battery 1-wire test at S 1706 . Here, a determination is made as to whether a connection between the power-pack and battery 1-wire exists and is authentic at S 1708 . If the connection between the power-pack and battery 1-wire exists but is not authentic (e.g., a 1-wire or authentication error results), use of the power-pack remains available, except for entering the firing state, a fault tone occurs, and an error screen is displayed at S 1710 . If the connection is authorized, a determination is made at S 1712  as to whether the testing is being performed during initialization. If so, a battery identifier (ID) is recorded in the memory at S 1714  so that the power-pack recognizes the recorded battery ID. As a result, if another battery with a different battery ID is used with the power-pack, an error screen is displayed and the power-pack is unable to operate with the unidentified battery. If the connection between the power-pack and battery 1-wire exists and is authentic and the test is not performed during initialization or if the ID has been recorded after detecting the initialization, the existence of a next test is determined at S 1702 , and if the next test exists, the next test is identified at S 1704 . If not, method  1700  ends. 
     If identified as being the next test to be performed, a clamshell 1-wire test is performed at S 1718 . At S 1720 , a determination is made regarding whether an outer shell housing is connected to the power-pack and whether the outer shell housing is authentic at S 1720 . In particular, a test across the outer shell housing 1-wire bus is performed to determine whether an outer shell housing is connected to the power-pack. If the outer shell housing is authentic, an identifier (ID) for the outer shell housing is obtained and recorded in the memory and the outer shell housing is marked as “used” in its memory at S 1710 . If there is an error detected or authentication fails, e.g., where the outer shell housing has previously been marked as “used,” use of the power-pack is possible except for entering the firing state, a fault tone occurs, and an error screen is displayed at S 1712 . Method  1700  advances to S 1702 , and if needed, S 1704 . 
     If not already performed, an adapter and reload 1-wire test is performed at S 1726 . Here, a test is performed across the adapter 1-wire bus to determine if an adapter and/or a reload is connected and whether they are authentic at S 1728 . If there is an error detected or authentication fails, a determination is made as to whether the failure is due to the adapter or reload at S 1730 . If the failure is due to the adapter, use of the power-pack is possible except for entering firing state, a fault tone occurs, and an “adapter” error screen is displayed at S 1732 . If the failure is due to the reload. Additionally, use of the power-pack is possible except for entering firing state, a fault tone occurs, and a “reload” error screen is displayed at S 1734 . 
     With reference again to  FIG. 73 , after the wire testing, method  1300  advances to S 1306 , where a determination is made as to whether any of the initialization tests have not been performed. If so, a next test is identified to be performed at S 1308 . If a number of uses remaining of the power-pack has not yet been verified, such operation is performed at S 1330 . In particular, a determination is made as to whether a firing counter is equal to or greater than a predetermined value representing a fire limit. The firing counter, stored in the memory of the power-pack, is obtained, and if the firing counter is equal to or greater than the fire limit, method  1500  is performed where the power-pack is operable except for entering firing state (S 1502 ), a fault tone occurs (S 1504 ), and a screen image communicating that no uses left is displayed (S 1506 ). After S 1330 , method  1300  returns to S 1306  and S 1308  to identify a next test to be performed, if any. If no test remains to be performed, method  1300  ends. 
     Prior to use, and in some instances, assembly, the battery of the power-pack is preferably charged, the performance of which is controlled by charging module  1116  ( FIG. 71 ). In an embodiment, upon connection to the charger, charging module  1116  provides instructions to the power-pack to release master control of a bus used to communicate with the battery. Although master control is released, the power-pack receives the time and is capable of updating the clock during connection to the charger. Connection with the charger may be made via electrical contacts associated with the battery circuit board  140 , communication therebetween may be accomplished over 1-wire bus  167  (see  FIG. 70 ). In an embodiment, the power-pack is not connected to the external communication system and does not enter the standby mode while charging. Information is available for display. For example, information from a previous procedure, a remaining firing count and/or procedure count, and/or remaining firing and autoclave counts in any attached adapter are available to be read by the user. Upon removal of the power-pack from the charger, the power-pack is restarted. 
     During assembly of the surgical device, validation module  1118  provides instructions for performing testing to detect whether a component (e.g., outer shell housing, adapter, or reload) being connected to the power-pack is valid.  FIG. 78  is a flow diagram of a method  1800  of validating the components, in accordance with an embodiment. Although any one of the validation tests can be initially performed, for the purposes of this description, outer shell housing validation with the power-pack is performed at S 1806 . In response to detecting engagement of an outer shell housing with the power-pack, the power-pack initiates a test, across the corresponding 1-wire bus, to determine whether the outer shell housing is valid at S 1808 . During the validation, a display screen indicating testing is displayed. If the outer shell housing is invalid or unsupported, a fault tone occurs and a “clamshell error” screen is displayed at S 1810 . In addition to determining validity, method  1800  includes identifying whether the outer shell housing has been previously used at S 1812 . In this regard, the memory of the outer shell housing is read for data, and the data is compared to data stored in the memory of the power-pack. If the outer shell housing has been previously used, method  1800  proceeds to S 1810  where a fault tone is sounded and an error screen is displayed on the display screen. In an embodiment, the power-pack is also inhibited from entering the firing state. 
     Returning to S 1808  and S 1812 , if a valid and unused outer shell housing is detected, the power-pack records the ID of the outer shell housing in the memory of the power-pack and marks the outer shell housing as used by writing such to its memory at S 1814 . Method  1800  then advances to S 1802  and, if needed, to S 1804  to identify a next test. 
     If not yet performed, the adapter is validated at S 1816 . The power-pack monitors the 1-wire bus at a minimum rate of 1 Hz for the presence of an adapter, and a “request adapter” screen is shown while waiting for the adapter, if a power-pack statistics is not already displayed on the display. In response to the detection of the adapter, the power-pack determines whether the adapter has a valid ID at S 1818  and is supported at S 1820 . If the adapter is unable to be identified, an error screen is displayed, a fault tone is sounded, and entering the firing state is inhibited at S 1822 . If the adapter is found to be unsupported, no further operation is permitted, a fault tone is sounded, and an error screen is displayed at S 1824 . If the adapter has a valid ID and is supported, the values of the two counters associated with the adapter are examined at S 1826 . Specifically, the power-pack reads the identifying and counter data from the attached adapter. In an example, with respect to the counters, the power-pack reads the firing count and an assumed autoclave count stored in the memory of the adapter and compares these values to the limits stored in the memory of the power-pack. If the adapter is found to have no remaining firings or no remaining autoclave cycles, a screen indicating the same is displayed and entering the firing state is inhibited at S 1828 . Otherwise, method  1800  advances to S 1802 , and if needed, S 1804 , for the identification of a next test to be performed. 
     In an embodiment, the next test to be performed includes validating a reload at S 1830 . Turning now to  FIG. 79 , the power-pack monitors the 1-wire communication bus to the adapter to detect whether a reload is attached and the type at S 1832 . For example, as detailed above, a switch of the adapter is actuated upon coupling of the reload thereto, providing a detectable indication to the power-pack that a reload is attached. 
     As noted above, different types of reloads can be attached to the adapter. For the purposes of this description, a first type of reload is ones that is not recognized as being a SULU-type reload, e.g., similar to SULU  400  ( FIG. 1 ), or a MULU-type reload, e.g., similar to MULU  900 B (FIGS.  69 B 1  and  69 B 2 ). This “first type” reload may be, for example, loading unit  900 A ( FIG. 69A ), loading unit  900 C ( FIG. 69C ), or loading unit  900 D ( FIG. 69D ). SULU-type reloads and MULU-type reloads are considered to be a “second type” of reload. SULUs and MULUs are readily identifiable and distinguishable by power-pack using the 1-wire communication system; however, for purposes of simplicity, both SULUs and MULUs are treated herein as being reloads of the second type. Further, although only two types of reloads, e.g., first types and second types, are detailed herein, it is understood that the power-pack can be configured to recognize any number of reload types. 
     If the first type of reload is detected, method  1800  advances to S 1834 , where the power-pack reads the memory of the reload in search of a reload ID. If a reload ID is detected, the power-pack tests the encryption of the reload ID at S 1836 . If at S 1834  or S 1836  either the reload ID is not recognized or the reload does not pass encryption, no operations are possible, a fault tone occurs, and a “reload error” screen is displayed at S 1838 . Otherwise, method  1800  advances to S 1802 , and if needed, to S 1804 . 
     Returning to S 1832 , if the second type of reload is detected, method  1800  advances to S 1850 , where a scan is made to determine whether the reload is capable of providing information, e.g., via a memory (with or without a processor) of the reload, RFID chip, barcode, symbolic label, etc., and/or the type of reload that is connected to the adapter. If the reload is determined not to be capable of providing information, the reload is identified as a legacy reload and a “check reload” screen is displayed at S 1852 . A check of whether the reload is connected properly is performed at S 1854 . If not connected properly, a fault tone occurs and a “reload error” screen is displayed at S 1856 . If the reload is connected properly, method  1800  returns to S 1802  and S 1804  (if needed) for the identification of a next test, if any. 
     If the reload is determined to be capable of providing information and/or the type of reload connected to the adapter is detected at S 1850 , the reload is considered a smart reload and an encryption of the smart reload is tested at S 1858 . If the encryption of the smart reload fails testing, operation can continue, except entering the firing state, the fault tone occurs, and the “reload error” screen is displayed at S 1860 . Similarly, if an unknown ID of the smart reload is detected or the 1-wire ID is detected by the reload switch is not property recognized, operation can continue, except entering the firing state, the fault tone occurs, and the “reload error” screen is displayed at S 1860 . 
     If encryption of the smart reload passes testing at S 1858 , a detection is made as to whether the second type of loading unit is a SULU, e.g., SULU  400  ( FIG. 1 ), or a MULU, e.g., MULU  900 B (FIGS.  69 B 1  and  69 B 2 ), at S 1862 . If a SULU is detected, the SULU is tested to detect whether it has been used at S 1864 . If it is determined to be used, the power-pack can be used, except entering firing state, a fault tone occurs, and a “reload error” screen is displayed at S 1860 . Otherwise, method  1800  returns to S 1802  and S 1804 , if needed. 
     If a MULU is detected, a firing counter of the MULU is read to determine whether the firing counter is greater than a fire limit at S 1866 . If the firing counter is greater than a fire limit, the “no uses left” screen is displayed and the power-pack can be used, except entering firing state at S 1868 . If the firing counter is not greater than the fire limit at  1860 , a scan is performed to detect a staple cartridge at S 1870 . If no staple cartridge is present, an “incomplete reload” screen is displayed at S 1872 . If a staple cartridge is present, method  1800  advances to S 1864 , to determine whether the staple cartridge has been used. Depending on the outcome at S 1864 , method  1800  may advance to S 1860  or S 1802  as described above. 
     Upon detection of a valid adapter with at least one use remaining and at least one autoclave cycle remaining, the operation functions are calibrated, instructions for which are provided by calibration module  1120 . The calibration process can differ depending on the particular type of adapter attached to the power-pack. 
       FIG. 80  is a flow diagram of a method  2000  of calibrating the articulation and firing functions of an adapter capable of attaching to a reload of the first type. A determination is made as to whether a reload is attached to the adapter at S 2002 . If a reload is attached to the adapter, calibration does not occur, an error screen is displayed, and a fault tone is sounded at S 2004 . If a reload is not attached to the adapter, a determination is made as to whether the software version stored in the adapter is compatible with the software of the power-pack at S 2006 . It will be appreciated that in another embodiment, calibration occurs regardless of whether a reload is attached, and hence in such an embodiment method  2000  begins from S 2006 . If the software version stored in the adapter is not compatible with the software of the power-pack, the power-pack updates the adapter software before calibration at S 2008 . At S 2010 , a determination is made as to whether the update is successful. If such update fails, firing calibration is performed but articulation calibration is not performed and entering the firing state is prohibited at S 2012 . If the software of the adapter and power-pack are found to be compatible at S 2006  or the software update is successful at S 2010 , calibration of the articulation function and the firing function occurs at S 2014 . Calibration of the articulation function involves obtaining a reference position by driving the articulation shaft left until it stops at its mechanical limit and then returning the articulation shaft back to the center position. Calibration of the firing function is effected by obtaining a reference position by driving the firing shaft proximally until it stops at its mechanical limit, followed by returning the firing shaft distally to its home position. 
     After performing the firing and articulation calibrations, a determination is made as to whether the calibration has been successful at S 2016 . If either the firing or articulation calibration fails at S 2016 , no further operation is permitted until the adapter is replaced or reconnected and calibration is properly obtained at S 2018 . If calibration is successful, the adapter is operable in the firing state at S 2020 . If a reload is subsequently detected as removed at S 2022 , a request reload screen is displayed at S 2024 . A determination is made as to whether movement has occurred since a calibration of the adapter at S 2026 . If so, an articulation centered occurs at S 2028 . If no movement has occurred since the last calibration at S 2026 , the firing rod is not moved to a home position and articulation will not be centered at S 2030 . Returning to S 2022 , if the reload has not been removed, the adapter remains operable in firing state at S 2020 . Any buttons pressed during adapter calibration are ignored. In an embodiment, calibration occurs despite the battery having an insufficient charge. In another embodiment, calibration occurs even when the adapter has no uses remaining. 
       FIG. 81  is a flow diagram of a method  2100  of calibrating an adapter configured to attach to a loading unit of the second type. Here, calibration module  1120  includes a feature to perform idle state calibration, where the adapter is not in a stapling or cutting state. First, a determination is made as to whether the software of the adapter is compatible at S 2102 . If not, power-pack updates the adapter software before calibration at S 2104 . At S 2106 , a determination is made as to whether the update is successful. If such update fails, no further operation is allowed, a fault tone occurs, and an error screen is displayed at S 2108 . 
     If the software of the adapter is found to be compatible at S 2102  or is successfully updated at S 2106 , a determination is made as to whether or not the adapter is idle at S 2110 . If the adapter is detected as in the idle state, the idle state calibration is performed at S 2112 . In particular, clamp shaft calibration is performed at S 2114  by obtaining a reference position by driving the clamp shaft proximally until it stops at its mechanical limit. In response to an endstop, the clamp shaft is driven distally to its home position. In addition to the clamp shaft calibration, a staple shaft calibration is performed at S 2116  by driving the staple shaft proximally until it stops at its mechanical limit. In response to an endstop, the staple shaft is driven distally to its home position. The pressing of any buttons during idle state calibration is ignored. Although the staple shaft calibration S 2116  is described as being performed after the clamp shaft calibration S 2114 , it will be appreciated that the calibrations can be performed in no particular order. If calibration is not performed successfully, no further operation is possible until the adapter is removed, a fault tone occurs, and an “adapter error” screen is displayed. 
     Returning to S 2110 , if the adapter is not in the idle state, a determination is made as to whether the adapter is in a stapling state or a cutting state at S 2118 . If the adapter is in the stapling state, stapling state calibration is performed at S 2120  by obtaining a reference position by driving the staple shaft proximally until it stops at its mechanical limit. The clamp and cut shaft calibration are not performed concurrently with the stapling state calibration, in an embodiment, and any button presses during stapling calibration are ignored. 
     If a cutting state is detected as S 2118 , calibration module  1120  performs a cutting state calibration at S 2128 . The cutting state calibration is performed by obtaining a reference position by driving the cut shaft proximally until it stops at its mechanical limit. The clamp and staple shaft calibration are not performed concurrently with the cutting state calibration, in an embodiment, and any button presses during stapling calibration are ignored. 
     A determination is made at S 2122  as to whether the stapling state and cutting state calibrations have been performed successfully. If the stapling state calibration is successful, a firing sequence continues from stapling at S 2124 . If the cutting state calibration is successful, a firing sequence continues from cutting at S 2124 . If either the stapling state or cutting state calibration is not performed successfully, no further operation is possible until the adapter is removed, a fault tone occurs, and an “adapter error” screen is displayed at S 2126 . 
     As described briefly above, operation is effectuated by utilizing the buttons disposed on outer shell housing  10  ( FIG. 1 ). Generally, operation module  1122  includes various modules to permit and inhibit various operations depending on the mode, status, state, and/or position of, among other components, the outer shell housing, the adapter, and the reload. The power-pack logs various data relating to the use and/or operation of the power-pack, the adapter, and the reload via communications transmitted across the 1-wire buses. Such data includes keystroke data relating to each of the buttons associated with the handheld, event logging data, fault and error data, knife position data, firing data, open/close data, etc.  FIG. 82  is a block diagram of operation module  1122  including its various modules, according to an embodiment. Operation module  1122  includes rotation module  2202 , articulation module  2204 , open module  2206 , close module  2208 , firing module  2210 , safety module  2212 , and counter module  2214 . 
     Rotation module  2202  causes rotation of the adapter in response to input received from pressing or actuating the appropriate button on surgical device  100  ( FIG. 1 ), as detailed above. Additionally, rotation is permitted before attaching the adapter. In the event in which the adapter is not connected, the power-pack statistics screen is displayed on the display for a predetermined duration (e.g., 5 seconds) after all buttons are released. Rotation also occurs with or without a reload connected, even where there is insufficient battery charge to fire, where no power-pack or battery uses are remaining, where the reload has been used, or where the reload is in a clamp position. If another button is pressed during rotation, rotation is halted until the button is released. Further, if under an excess load is detected, rotation is stopped until the rotation button is released and re-depressed. Rotation is stopped in response to a detection of a motor velocity of 0 rotations per minute (RPMs) and remains stopped until button depression is detected again. 
     Articulation module  2204  articulates the reload. For example, in response to signals received from the appropriate button on surgical device  100  ( FIG. 1 ), the reload is articulated either left or right. Articulation is permitted where there is insufficient battery charge to fire, where no power-pack or battery uses are remaining, where the reload is connected, or where the reload has been used and/or has no uses remaining. Depression of another button during articulation causes articulation to stop until the button is released. Articulation module  2204  includes an articulation current limit defined and set by adjusting the limit control on the motor controller circuit. The articulation current limit correlates to a maximum torque the motor will output. When a velocity threshold (e.g., of about −200 RPM±−5%) is reached or exceeded, articulation is stopped. Depression of any of the articulation buttons prior to attachment of the adapter and the reload does not cause articulation. In an embodiment, when the reload is in the clamp or closed position, articulation is effected at a slower rate as compared to articulation in the open position (e.g., 200 RPM±10 RPM). 
     Open module  2206  controls the opening of reload, in response to a pressing of the open button and determines whether opening operation continues or not based on various scenarios. For example, pressing the open button before the adapter or the reload is attached is ignored. During a reload opening, the reload remains open until the open button is released or the reload is fully opened. Opening is permitted with insufficient battery charge, with no power-pack or battery uses are remaining, or where the reload has been used. If another button is pressed during opening, opening is halted until the button is released. In an embodiment in which a trocar is used in conjunction with the surgical device, the trocar extends until fully extended, in response to an input received from a pressed open button. If the trocar is unable to be extended, no further operation is allowed, a fault tone occurs, and the “reload error” screen is displayed. 
     Close module  2208  controls the closing of reload, in response to a pressing of the close button and determines whether a close operation continues or not based on various detected or received inputs. In an embodiment, pressing the close button before the adapter or the loading is attached is ignored. Closing is effectuated until the close button is released or the fully closed position is achieved, at which time a tone is caused to be sounded. A closing operation is permitted where there is insufficient battery charge to fire, where no power-pack or battery uses are remaining, or where the reload has been used. If another button is pressed during closing, closing is halted until the button is released. A speed current limit is defined and set on the motor based on strain gauge. The speed current limit correlates to a maximum torque the motor will output. When a velocity threshold (e.g., of about −200 RPM±−5%) is reached or exceeded, the closing speed is reduced. 
     Firing module  2210  controls firing of staples in the reload by placing the reload in a firing state (during which staples can be fired) or out of the firing state (during which staples cannot be fired). In an embodiment, entering the firing state is only permitted when each of the following conditions is met:
         the outer shell housing has been installed, detected, verified as acceptable, and has not been used on a previous procedure;   the adapter has been installed, detected, verified as acceptable, and calibrated successfully;   the reload has been installed, verified as acceptable, passed encryption, can be marked as used, and has not been previously fired; and   the battery level is sufficient for firing.
 
After the above conditions are met, and an input is detected indicating that the safety has been pressed, the power-pack enters the firing state and the attached the reload is marked as used its memory. While in in the firing state, pressing the close button advances the stapler pusher and knife to eject the staples through tissue and cut the stapled tissue, until the close button is released or the end stop of the reload is detected. If an endstop is detected, releasing and pressing the fire button again shall continue to advance the knife until the fire button is released or an end stop is again detected. Firing may continue upon re-actuation until forward progress is no longer made between end stops.
       

     When the fire button is released and the open button is pressed twice, at any point during firing, the power-pack exits the firing state and the knife is automatically retracted to its home position. If the open button is pressed a single time during firing, i.e., while the fire button is pressed, firing stops. Firing does not continue until both the fire and open buttons have been released and the fire button is pressed again. 
     In the firing state, three speeds are provided: slow, normal, and fast. Rotation of adapter is inhibited in the firing state and, thus, the rotation buttons do not effect rotation. Rather, in the firing state, the rotation buttons are actuatable to increase or decrease the firing speed. The firing speed is initially set to normal. Articulation is also inhibited when in the firing state. 
     Loss of 1-wire communication between the power-pack and outer shell housing and/or adapter, or loss of communication regarding reload presence, does not interrupt firing. However, such communication is checked after firing and retraction have been completed. 
     If the firing state is exited before any forward progress is made, reentering firing state does not increment the power-pack firing counter. Further, if the firing limit of the power-pack or adapter has been reached during an operation, the firing state remains accessible until the attached outer shell housing or adapter is removed. 
     If the firing state is exited before any forward progress is made, reentering firing state does not increment the power-pack firing counter. Further, if the firing limit of the power-pack or adapter has been reached during an operation, the firing state remains accessible until the attached outer shell housing or adapter is removed. 
     During the firing state, if linear sensor data no longer returns during a stapling sequence, stapling is interrupted, a fault tone occurs, and an “adapter error” screen is displayed. Additionally, if no movement of the staple shaft or the cut shaft is detected for a predetermined period of time (e.g.,  1  second), stapling or cutting stops, a fault tone occurs, and a “reload error” screen is displayed. If an excessive load is detected during a stapling or cutting sequence, the stapling or cutting ceases, a fault tone occurs, and a “power-pack error” screen is displayed. In an embodiment in which an insufficient load is detected during a stapling or cutting sequence, the stapling or cutting ceases, a fault tone occurs, and a “power-pack error” screen is displayed. 
     Safety module  2212  controls entry of surgical device  100  ( FIG. 1 ) into the firing state. Specifically, the firing state is entered when safety module  2212  detects that:
         an outer shell housing is installed, detected and supported;   an adapter is installed detected, supported, and successfully calibrated;   SULU or MULU is installed, detected, supported, and passed encryption;   MULU cartridge is installed and has not been fired;   SULU or MULU cartridge can be marked as used;   reload is installed and detected;   reload has not previously fired;   battery level is sufficient for firing; and   the outer shell housing has not been used on a previous procedure.
 
In an embodiment, a safety LED is lit when the power-pack is fully assembled and not in an error condition. When entering the firing state, a tone occurs and a “firing” screen is displayed, and the safety LED flashes until the firing state is exited. The firing state is exited when the open key is pressed, for example, twice, and a tone indicating exiting firing mode is displayed. The safety LED is not lit if the power-pack is unable to enter the firing state or when firing is complete.
       

     Counter module  2214  maintains various counters that increment upon occurrence of specific events or conditions to indicate when certain components have reached the end of their usable lives. In particular, counter module  2214  maintains a power-pack procedure counter, a power-pack firing counter, an assumed autoclave counter for the adapter, and an adapter firing counter. These counters are in addition to the “used” markings assigned to outer shell housing and SULU, which are single-procedure-use components. 
     The power-pack procedure counter is stored in the memory of the power-pack. The power-pack procedure counter is incremented when the firing state is first entered after attaching a new outer shell housing to the power-pack. The power-pack procedure counter is not again incremented until the outer shell housing is removed a new outer shell housing installed and the firing state again entered, regardless of whether the firing state is entered multiple times while housed in a single outer shell housing. If the power-pack procedure counter cannot be incremented, power-pack can operate except in firing state, a fault tone occurs, and a “power-pack error” screen is displayed. 
     The power-pack firing counter is stored in the memory of the power-pack. The power-pack firing counter is incremented each time the firing state is entered except that, if the firing state is entered and no forward progress is made, reentering the firing state does not increment the power-pack firing counter. If the power-pack firing counter limit has been arrived at, power-pack is inhibited from entering the firing state. If the power-pack firing counter cannot be incremented, power-pack can operate except in firing state, a fault tone occurs, and a “power-pack error” screen is displayed. 
     The adapter autoclave counter is stored in the memory of the adapter and is incremented when the firing state is first entered after attaching a new outer shell housing. Due to the adapter being a reusable component, the adapter has a pre-set limit on usages, and it is assumed that the adapter is autoclaved prior to each procedure. If the adapter autoclave counter has already been incremented for a particular attached outer shell housing, it will not be incremented again until the outer shell housing is removed and replaced. If the adapter autoclave counter cannot be incremented, power-pack can operate except in firing state, a fault tone occurs, and an “adapter error” screen is displayed. 
     The adapter firing counter is stored in the memory of the adapter and is incremented when entering the firing state except that, if the firing state is entered and no forward progress is made, reentering the firing state does not increment the adapter firing counter. If the adapter firing counter limit has been arrived at, power-pack can operate except in firing state, a fault tone occurs, and a “power-pack error” screen is displayed. 
     In accordance with the present disclosure, in order to evaluate conditions that affect staple formation, such that a more intelligent stapling algorithm, may be developed, an electromechanical testing system may be used in place of a surgical device or stapler (e.g., powered hand held electromechanical instrument  100 ). The electromechanical testing system may be configured to deploy (e.g., fire) staples on ex vivo porcine stomach to measure forces and the resulting staple formation data may be collected. A sequential design of experiments may be utilized to assess the effects of four different factors, including speed of firing, tissue thickness, precompression time, and stapler length with respect to firing force and staple formation. 
     It was discovered that the firing force was affected by the speed of firing, a length of the reload (e.g., stapler length) and the tissue thickness. It was also discovered that staple formation was affected by the speed of firing and the tissue thickness. Finally, a correlation was discovered between the force on the electromechanical testing system and the staple formation; specifically, lower forces on the electromechanical testing system yielded better staple formation (e.g., fewer mis-formations, great complete formations, etc). 
     By slowing the speed of firing, particularly when relatively high forces are seen within a stapling system (e.g., surgical device or stapler, or powered hand held electromechanical instrument  100 ), the performance of the surgical device is improved It is contemplated that variations in the software are available to optimize output based on different reload types and in a variety of tissues with different characteristics (e.g., density, thickness, compliance, etc.). The intelligent stapling systems may be configured to continue to utilize clinical data and enhance device performance, leading to improved patient outcomes, by updating and/or modifying firing algorithms associated therewith. 
     With reference to  FIGS. 83-88 , another embodiment of an adapter assembly, according to the present disclosure, is illustrated as  500 . The adapter assembly  500  is substantially similar to the adapter assembly  200  of  FIGS. 1 and 20-26 . Thus, only certain features of a switch actuation mechanism  510  of the adapter assembly  500  will be described in detail. The adapter assembly  500  includes a knob assembly  502  and an elongate body or tube  506  extending distally from a distal portion of the knob assembly  502 . The knob assembly  502  is configured to connect to a handle housing, such as the handle housing  102  of the surgical device  100  ( FIG. 1 ). The elongate body  506  houses various internal components of the adapter assembly  500 , such as the switch actuation mechanism  510 , and includes a proximal portion  506   a  coupled to the knob assembly  502  and a distal portion  506   b  configured to couple to a loading unit, such as the loading unit  400  ( FIGS. 53 and 54 ). 
     The switch actuation mechanism  510  of the adapter assembly  500  toggles a switch (not explicitly shown) of the adapter assembly  500  upon successfully connecting the loading unit  400  to the adapter assembly  500 . The switch, which is similar to the switch  320  of  FIG. 48  described above, is configured to couple to a memory of the SULU  400 . The memory of the SULU  400  is configured to store data pertaining to the SULU  400  and is configured to provide the data to a controller circuit board of the surgical device  100  in response to the SULU  400  being coupled to the distal portion  506   b  of the elongate body  506 . As described above, the surgical device  100  is able to detect that the SULU  400  is engaged to the distal portion  506   b  of the elongate body  506  or that the SULU  400  is disengaged from the distal portion  506   b  of the elongate body  506  by recognizing that the switch of the adapter assembly  500  has been toggled. 
     With reference to  FIGS. 84-88 , the switch actuation mechanism  510  of the adapter assembly  500  includes a switch actuator  540 , a distal link  550  operably associated with the switch actuator  540 , an actuation bar  584 , and a latch  586  each of which being disposed within the elongate body  506 . In some embodiments, some or all of the components of the switch actuation mechanism  510  may be disposed on an outer surface of the elongate body  506  rather than inside. 
     The switch actuator  540  is longitudinally movable between a distal position, as shown in  FIGS. 85-88 , and a proximal position (not shown). In the distal position, a proximal portion  540   a  of the switch actuator  540  is disassociated from the switch (not explicitly shown), and in the proximal position the proximal portion  540   a  of the switch actuator  540  toggles or actuates the switch (not explicitly shown). It is contemplated that any suitable portion of the switch actuator  540  may be responsible for toggling the switch. 
     The switch actuator  540  is resiliently biased toward the distal position via a biasing member (e.g., a coil spring not explicitly shown), similar to the spring  348  of  FIG. 48  described above. As such, the switch actuator  540  is biased toward engagement with the switch. The switch actuator  540  includes a distal portion  540   b  having a mating feature, such as, for example, a tab  542  extending laterally therefrom. The tab  542  of the switch actuator  540  detachably lockingly engages the latch  586  during loading of the loading unit  400  into the adapter assembly  400 , as will be described in detail below. 
     The distal link  550  of the switch actuation mechanism  510  is aligned with and disposed distally of the distal portion  540   b  of the switch actuator  540 . The distal link  550  is longitudinally movable within and relative to the elongate body  506  between a distal position, as shown in  FIGS. 84-87 , and a proximal position, as shown in  FIG. 88 . The distal link  550  has a proximal portion  550   a  operably associated with the distal portion  540   b  of the switch actuator  540 , and a distal portion  540   b  for interacting with a second lug  412   b  of the loading unit  400  during insertion of the loading unit  400  into the elongate body  406  of the adapter assembly  400 . The switch actuation mechanism  510  includes a biasing member, such as, for example, a coil spring  548 , disposed between the distal portion  540   b  of the switch actuator  540  and the proximal portion  550   a  of the distal link  550 . The coil spring  548  couples the switch actuator  540  and the distal link  550  together such that longitudinal movement of one of the switch actuator  540  or the distal link  550  urges a corresponding motion of the other of the switch actuator  540  or the distal link  550 . 
     The actuation bar  584  of the switch actuation mechanism  510  is longitudinally movable between a distal position, as shown in  FIGS. 85 and 86 , and a proximal position, as shown in  FIGS. 87 and 88 . In the distal position, a distal portion  584   b  of the actuation bar  584  is engaged to or otherwise associated with the latch  586  or allow the latch  586  to be released to release the latch  586  from the switch actuator  540 , and in the proximal position the distal portion  584   b  of the actuation bar  584  is disengaged or disassociated from the latch  586  to allow the latch  586  to lockingly engage the switch actuator  540 . The actuation bar  584  has a projection or tab  588  extending laterally from the distal portion  584   b  thereof. The tab  588  of the actuation bar  584  is configured to contact and move the latch  586  when the actuation bar  584  is moved from the proximal position toward the distal position. 
     The distal portion  584   b  of the actuation bar  584  includes a distally-extending extension  590  for interacting with the second lug  412   b  of the loading unit  400  during insertion of the loading unit  400  into the distal portion  506   b  of the elongate body  506 . The actuation bar  584  is resiliently biased toward the distal position via a biasing member, e.g., a coil spring  592  ( FIG. 84 ). As such, the actuation bar  584  is resiliently biased toward a state in which the tab  588  of the actuation bar  584  is engaged with the latch  586 . 
     The latch or arm  586  of the switch actuation mechanism  510  is pivotably coupled to an internal housing or support structure  594  disposed within the elongate body  506 . The latch  586  is elongated and has a proximal portion  586   a  associated with the switch actuator  540  and a distal portion  586   b  associated with the actuation bar  584 . The proximal portion  586   a  of the latch  586  has a hooked configuration and includes a mating feature, such as, for example, a groove  596  defined therein. The groove  596  is dimensioned for receipt of the tab  542  of the switch actuator  540 . In embodiments, the distal portion  540   b  of the switch actuator  540  may have the groove  596  rather than the tab  542 , and the proximal portion  586   a  of the latch  586  may have the tab  542  rather than the groove  596 . The distal portion  586   b  of the latch  586  also includes a mating feature, such as, for example, a projection  587  that defines a ramped surface  589  for engaging the tab  588  of the actuation bar  584  during distal movement of the actuation bar  584 . 
     The latch  596  is pivotable relative to the support structure  594  between a first position, as shown in  FIGS. 85 and 86 , and a second position, as shown in  FIGS. 87 and 88 . In the first position, the proximal portion  586   a  of the latch  586  is oriented away from and out of engagement with the tab  542  of the switch actuator  540 . The latch  586  enters and/or is maintained in the first position when the tab  588  of the actuation bar  584  is engaged with the projection  587  of the distal portion  586   b  of the latch  586  due to the actuation bar  584  being in the distal position. 
     The latch  586  is resiliently biased toward the second position via a biasing member, such as, for example, a leaf spring  598  fixed to the support structure  594  disposed within the elongate body  506 . As such, the leaf spring  598  urges the proximal portion  586   a  of the latch  586  into engagement with the tab  542  of the switch actuator  540 . The latch  586  may enter the second position, via the biasing force of the leaf spring  598 , when the tab  588  of the actuation bar  584  is disposed in the proximal position out of engagement with the projection  587  of the distal portion  586   b  of the latch  586 . 
     In operation, with reference to  FIG. 86 , the SULU  400  is oriented such that the first lug  412   a  thereof is aligned with the actuation bar  584  of the adapter assembly  500  and the second lug  412   b  thereof is aligned with the distal link  550  of the adapter assembly  500 . The SULU  400  is inserted into the distal portion  506   b  of the elongate body  506  of the adapter assembly  500  to engage the first lug  412   a  of the SULU  400  with the extension  590  of the distal portion  584   b  of the actuation bar  584 . At this stage of loading the SULU  400  into the adapter assembly  500 , the actuation bar  584  of the switch actuation mechanism  510  remains in the distal position, in which the tab  588  of the actuation bar  584  is engaged with the projection  587  of the distal portion  586   b  of the latch  586 , thereby maintaining the latch  586  in the first position. 
     Also at this stage of loading the SULU  400  into the adapter assembly  500 , the extension  590  of the distal portion  584   b  of the actuation bar  584  extends distally beyond the distal portion  550   b  of the distal link  550  a distance “Z.” Since the extension  590  of the distal portion  584   b  of the actuation bar  584  projects distally beyond the distal portion  550   b  of the distal link  550 , the second lug  412   b  of the SULU  400  is not yet engaged with the distal portion  550   b  of the distal link  550 , as shown in  FIG. 86 . 
     Further insertion of the SULU  400  within the elongate body  506  of the adapter assembly  500  starts to translate the actuation bar  584  in a proximal direction, as indicated by arrow “G” in  FIG. 86 . Proximal translation of the actuation bar  584  disengages the tab  588  of the distal portion  584   b  of the actuation bar  584  from the projection  587  of the distal portion  586   b  of the latch  586 , as shown in  FIG. 87 , to allow the leaf spring  598  to pivot the proximal portion  586   a  of the latch  586  toward the tab  542  of the switch actuator  540 , in the direction indicated by arrow “H” in  FIG. 87 . The tab  542  of the distal portion  540   b  of the switch actuator  540  is received within the groove  596  of the proximal portion  586   a  of the latch  586  such that the latch  586  prevents the switch actuator  540  from moving proximally relative thereto. 
     Upon the actuation bar  584  translating in the proximal direction the distance “Z,” which occurs after or concurrently with the latch  586  locking with the switch actuator  542 , the second lug  412   b  of the SULU  400  engages the distal portion  550   b  of the distal link  550  of the switch actuation mechanism  510 , as shown in  FIG. 87 . Thus, further insertion of the SULU  400  into the elongate body  506  of the adapter assembly  500  starts to translate the distal link  550  in the proximal direction, as shown in  FIG. 88 . Due to the switch actuator  540  being locked in the distal position by the latch  586 , the proximal translation of the distal link  550  does not move the switch actuator  540 . Instead, the distal link  500  moves toward the switch actuator  540  to compress (e.g., load) the biasing member  548  disposed therebetween. At this stage of loading the SULU into the elongate body  506  of the adapter assembly  500 , the SULU  400  is not locked to the adapter assembly  500  and the switch of the adapter assembly  500  is not toggled. 
     To complete the loading process, the SULU  400  is rotated relative to the elongate body  506 . Rotating the SULU  400  moves the first lug  412   a  of the SULU  400  out of engagement with the extension  590  of the actuation bar  584  to allow the distally-oriented biasing force of the biasing member  592  ( FIG. 84 ) of the actuation bar  584  to distally translate the actuation bar  584 , which captures the first lug  412   a  of the SULU  400  between a distal cap  507  of the elongate body  506  and the extension  590  of the actuation bar  584 . In addition to locking the SULU  400  to the elongate body  506 , the distal translation of the actuation bar  584  also moves the tab  588  of the distal portion  584   b  of the actuation bar  584  back into engagement with the projection  587  of the distal portion  586   b  of the latch  586 , whereby the latch  586  pivots, in the direction indicated by arrow “I” in  FIG. 88 , to release the tab  542  of the switch actuator  540  from the groove  596  of the proximal portion  586   a  of the latch  586 . 
     Upon unlocking the switch actuator  540  from the latch  586 , the proximally-oriented force of the loaded coil spring  548  is allowed to act on the switch actuator  540  to translate the switch actuator  540  in the proximal direction away from the distal link  550 , which remains in the proximal position due to the engagement with the second lug  412   b  of the SULU  400 . As the switch actuator  540  moves into the proximal position (not shown), the proximal portion  540   a  of the switch actuator  540  engages and toggles the switch of the adapter assembly  500  to indicate to the adapter assembly  500  that the SULU is successfully attached thereto. The proximal translation of the switch actuator  540  also compresses (e.g., loads) the biasing member (not shown) of the switch actuator  540 . 
     To selectively release the SULU  400  from the adapter assembly  500 , a clinician may translate or pull a release lever  513  ( FIGS. 83 and 84 ) disposed on the knob assembly  502  of the adapter assembly  500 . The release lever  513  is directly coupled to the proximal portion  584   a  of the actuation bar  584  such that proximal movement of the release lever  513  causes the actuation bar  584  to move proximally. Proximal movement of the actuation bar  584  moves the distal portion  584   b  of the actuation bar  584  out of engagement (or out of blocking axial alignment) with the first lug  412   a  of the SULU  400  and the SULU  400  can be rotated. 
     While holding the release lever  513  in the proximal position, and consequently the actuation bar  584 , the SULU  400  may then be rotated and translated distally out of the elongate body  506 . As the SULU  400  is removed from the elongate body  506 , the actuation bar  584  moves distally under the distally-oriented bias of the coil spring  592 , and both the distal link  550  and the switch actuator  540  move distally under the distally-oriented bias of the biasing member (not shown) of the switch actuator  542 , which was loaded during the proximal translation of the switch actuator  540  while loading the SULU  400 . As the switch actuator  540  is urged in the distal direction, the proximal portion  540   a  of the switch actuator  540  disengages the switch to notify the adapter assembly  500  that the SULU  400  is released therefrom. 
     It will be understood that various modifications may be made to the embodiments of the presently disclosed adapter assemblies. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure.