Abstract:
A system and method for interconnecting analog legacy stores to both legacy and modern aircraft. One aspect of the invention provides for a dual mode launcher having a first interface for interfacing with a modern aircraft and a second interface for interfacing with a legacy aircraft. Either the first or the second interface is connected to the aircraft depending on the hardware platform supported by the aircraft. Signals received from either interface are converted to digital and placed on a digital input/output bus and converted to analog for use by the store. Likewise, signals transmitted by the store to the aircraft are converted to digital and placed on the digital input/output bus for transmission to the aircraft. The signals are further acted upon depending upon which interface is connected to the dual mode launcher assembly. The dual mode launcher provides seamless operation of the store interface regardless of which type of aircraft is equipped to carry the analog store.

Description:
TECHNICAL FIELD 
   The present invention relates generally to aircraft and aircraft stores. More specifically, the present invention relates to a dual mode interface for interconnecting analog legacy stores to both legacy and modern aircraft. 
   BACKGROUND OF THE INVENTION 
   Until recently, an aircraft and the stores which it carried were typically developed independently of each other or were developed exclusively for each other. This practice usually resulted in unique aircraft/store electrical interconnection requirements, the general proliferation of overall store interface designs, low levels of interoperability, and costly aircraft modifications to achieve required store utilization flexibility. Trends in store technology toward more complex store functions requiring increasing amounts of avionics data and control information from aircraft systems were predicted to lead to a multitude of aircraft/store interfacing problems. 
   In late 2003, the U.S. Department of Defense promulgated MIL-STD-1760 revision D (hereinafter referred to MIL-STD-1760). The stated goal of MIL-STD-1760 is to develop aircraft that are compatible with a wide variety of stores and stores that are compatible with a wide variety of aircraft. MIL-STD-1760 accomplishes this goal by defining a standard electrical (and fiber optic) interconnection system for aircrafts and stores. This interconnection system is based on the use of a standard connector, a standard signal set and a standard serial digital interface for control, monitor, and release of stores. 
   Newly produced tactical aircraft are internally wired with the MIL-STD-1553 databus for coupling to the MIL-STD-1760 standard weapons interface. Modern smart weapons such as the Joint Direct Attack Munition (JDAM) are designed to communicate with the aircraft via such interface to obtain control, monitor and release information from the aircraft in order to carry out mission critical operations. 
   Unfortunately, the overwhelming majority of legacy stores in use today are not properly equipped to interface with the MIL-STD-1760 interface of modern tactical aircraft. One such legacy store is the Maverick family of missiles. Maverick missiles are one of the most versatile, precision strike missiles of all time. The Maverick&#39;s versatility, is in part, due to its ability to be fired from a number of aircraft against a variety of targets such as field fortifications, bunkers, hangarettes, tanks, armored personnel carriers, parked aircraft, radar or missile sites, port facilities, and ships, including high-speed patrol craft. Maverick&#39;s versatility is further enhanced by its guidance capabilities, which include a combination of TV, laser, and infrared guidance systems that allow for strategic operations to be conducted in day and night operations in a variety of atmospheric conditions. 
   Since the Maverick missile was developed during the early to mid-1970&#39;s, before the onslaught of digital electronics, Mavericks, like many legacy stores, are based on an analog system that requires extensive wiring, unique dedicated hardware and software, and specialty video processing circuitry in the host aircraft to fully integrate the store to the aircraft. Thus, a shortcoming associated with analog stores is that some type of interface is needed to enable the analog store to be used in connection with modern aircraft, while at the same time maintaining legacy store compatibility with legacy aircraft. 
   In view of the aforementioned shortcomings associated with the interface between legacy stores and modern aircraft, there is a strong need in the art for a dual interface between legacy stores and aircraft to overcome the problems set forth above. Moreover, there is a strong need in the art to maintain legacy store compatibility with legacy aircraft. 
   SUMMARY OF THE INVENTION 
   The present invention relates to a dual mode launcher that provides an interface from a modern aircraft or a legacy aircraft to a legacy store. 
   In one embodiment, the present invention relates to a launcher for providing communications between an associated aircraft and a legacy store, the launcher including: a first interface for receiving a digital control and a digital data signal from an aircraft; a means for converting the digital control signal or the digital data signal to an analog signal corresponding to digital control signal or the digital data signal; a store interface for communicating the analog signal to an associated store; and a means for providing information originating from the associated store for use by the associated aircraft through the first interface. 
   In another embodiment, the present invention relates to a launcher for launching an associated store from an associated aircraft, the launcher including: a dual mode launcher assembly for launching an associated store from an associated aircraft; a first interface and a second interface connected housed in at least a portion of the dual mode launcher assembly, wherein the first interface and the second interface are capable of exchanging information between the launcher and an associated aircraft having a hardware configuration, wherein either the first interface or the second interface is communicatively coupled to the associated aircraft based upon the hardware configuration of the associated aircraft; the dual mode launcher assembly further including a third interface for communicatively coupling the launcher to the associated store, in order to exchange information between the launcher and the associated store. 
   In another embodiment, the present invention relates to a method for communicating information between an associated aircraft and an associated store, the method including: selecting a first interface or a second interface of a launcher to communicatively coupled the launcher to an associated aircraft having a hardware configuration, wherein the selected interface is determined based upon the hardware configuration of the associated aircraft; communicatively coupling the launcher to an associated store through a third interface, wherein the third interface is capable of exchanging information between the launcher and the associated store, receiving information from the first or second interface; converting the received data from the associated aircraft to analog signals provided to the associated store; and converting analog signals originating from the associated store to digital signals provided to the associated aircraft. 
   In another embodiment, the present invention relates to a method for communicating information between an associated aircraft and an associated store, the method including: receiving at least one analog signal from an associated store, wherein the at least one analog signal relates to a physical characteristic of the associated store; converting at least one of the at least one analog signal received from the associated store to at least one digital signal corresponding to the physical characteristic of the associated store; and translating the at least one digital signal corresponding to the physical characteristic of the store for use by an associated aircraft having a digital interface. 
   In another embodiment, the present invention relates to a method for communicating information between an associated aircraft and an associated store, the method including: receiving information in the form of at least one digital signal from an associated aircraft; converting the at least one digital signal received from the associated aircraft to a least one analog signal; and translating the at least one digital signal corresponding to the information received from the associated aircraft for use by an associated store. 
   Other systems, methods, features, and advantages of the present invention will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Many aspects of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Likewise, elements and features depicted in one drawing may be combined with elements and features depicted in additional drawings. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
       FIG. 1  is a schematic fragmented elevational view of an aircraft with a launcher and an associated store removably affixed to its wing; 
       FIGS. 2A and 2B  are a block diagrams of the logical architecture of a dual mode launcher assembly in accordance with one aspect of the present invention; and 
       FIG. 3  is a block diagram of the physical architecture of the dual mode launcher assembly in accordance with one aspect of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. 
   Referring now to  FIG. 1 , a portion of an aircraft  10  having a fuselage  12  and a wing  14  extending therefrom is shown. The aircraft  10  can be any type of aircraft, including, fighter jets (e.g., the A-10, F-15 and F-16) and helicopters (e.g., AH-64 and AH-1). Extending downwardly from the wing  14  is a bomb rack  16 , a launcher  18  attached to the bomb rack  16 , and a store  20  (also commonly referred to as a missile) supported from the launcher  18 . The bomb rack  16  can be any type of bomb rack, including bomb racks capable of storing a single store or multiple stores. Likewise, while the launcher  18  has been described as being attached to the bomb rack, the launcher  18  may instead be supported from the fuselage  12  or the launcher  18  may extend from a wingtip or other location on the aircraft  10 . 
   The store  20  may be any type of store capable of being carried by an aircraft  10 , including an air-to-air missile or an air-to-surface missile. As an example, the store  20  is a member of the Maverick family of missiles, manufactured by the assignee of the present application, Raytheon Company of Lexington, Mass. 
   As shown in  FIG. 1 , a dual mode launcher assembly  30  comprises at least a portion of the launcher  18 . The dual mode launcher assembly  30  may be removably attached to the launcher  18  or may be integral to the launcher  18 . Preferably, the dual mode launcher assembly  30  is housed within the launcher  18 . However, the dual mode launcher assembly  30  may also be housed externally to the launcher  18  (e.g., the dual mode launcher assembly  30  may be located on the wing  14 , the fuselage  12  or within the store  20 ). 
   Referring to  FIGS. 2A and 2B , block diagrams of the logical architecture of the dual mode launcher assembly  30  in accordance with one aspect of the present invention is shown. The dual mode launcher assembly  30  includes an analog interface  32  (also referred to as a legacy interface) and a digital interface  34  (also known as an MIL-STD-1760 compliant interface). Each of these interfaces may be used to interconnect the dual mode launcher assembly  30  to the aircraft  10 . The selection of the appropriate interface (analog  32  or digital  34 ) is based upon the type of aircraft  10  in which the launcher and store is connected. For example, if the aircraft  10  is designed for an analog interface to the launcher  18  and associated store  20 , the analog interface  32  will be used connect the dual mode launcher assembly  30  to the aircraft  10 . Likewise, if the aircraft  10  is designed for a digital interface to the launcher  18  and associated store  20 , the digital interface  34  will be used to connect the dual mode launcher assembly  30  to the aircraft  10 . 
   The dual mode launcher assembly  30  further includes a store interface connector  36  for communicating various signals (e.g., command, status and video) between the dual mode launcher assembly  30  and an associated store  20 . As discussed in more detail below, the dual mode launcher assembly  30  permits aircrafts having a digital interface or an analog interface to seamlessly communicate with a legacy store. 
   Referring to  FIGS. 2A and 2B , information received from either the analog interface  32  or the digital interface  34  is converted to a digital signal to be placed on the digital input/output bus  38 . The digital input/output bus  38  is utilized to communicate signals from the analog interface  32  and the digital interface  34  to the store interface  36 . The store interface connector  36  is also capable of transmitting signals (e.g., status and video) from the associated store  20  to the appropriate analog interface  32  or digital interface  34  through the digital input/output bus  38 . Since the legacy store  20  is generally an analog system, the signals originating from the store  20  are converted to digital signals prior to transmission to the digital input/output bus  38 . If the digital signals are required to be communicated to the analog interface  32 , the digital signals are converted to analog for use by the aircraft  10 . The operation of the digital input/output bus  38  is controlled by the CPU power PC  50 . 
   As stated above, aircraft  10  communicates to an associated store  20  either through an analog (legacy) interface  32  or a digital interface  34  (compliant with MIL-STD-1760). If the communication between the aircraft  10  and the store  20  is required to be analog, the store  20  will interface to aircraft  10  through store interface  36  and analog interface  32 . Likewise, if digital communications is required, aircraft  10  and store  20  will interface through store interface  36  and digital interface  34 . When a particular connector (not shown) for the analog interface  32  or the digital interface  34  is not in use, the connector may be conveniently stowed within the body of the launcher  18 , or in some other convenient location. For example, if the aircraft  20  is expecting to receive analog signals from the store  20 , the connector associated with the digital interface  34  is stowed in the launcher  18 . Likewise, if the aircraft  10  is expecting to receive digital signals from the store  20 , the connector associated with the analog interface  32  is stowed in the launcher  18 . 
   The dual mode launcher assembly  30  outputs signals to the store interface  36  that matches the signals that the store  20  is expecting. Regardless of the interface source (analog interface  32  or digital interface  34 ), the received data by the dual mode launcher assembly  30  is converted or synthesized for use on the digital input/output bus  38 . Once the received data is placed on the input/output bus  38 , the data may be subsequently converted to analog for use by the store  20 . For instance, if the aircraft  10  is connected to digital interface  34 , the dual mode launcher assembly  30  synthesizes the data (adjusts amplitude), places the data on the input/output bus  38  and subsequently translates those digital signals received from the aircraft  10  to correspond to the analog signals that the store  20  is expecting. Likewise, if the aircraft  10  is connected to analog interface  32 , the dual mode launcher assembly  30  converts the data to digital, places the data on the input/output bus  38  and subsequently translates the digital signals corresponding to the analog signals received from the aircraft  10  to the analog signals that the store  20  is expecting. 
   Operation of the dual mode launcher assembly  30  will now be discussed. Operation of the dual mode launcher assembly  30  in analog or legacy mode will duplicate the external interface characteristics of the legacy launcher. For example, when the store  20  is a Maverick missile, the dual mode launcher assembly  30  will duplicate the external interface characteristics of the LAU-117A(V)3/A Launcher (the Maverick native (or legacy) analog interface). 
   As shown in  FIGS. 2A and 2B , various input signals are received at discrete input  40  from the analog interface  32 . These signals include: LAUNCH, DOME COVER POWER, STATION SELECT, SLAVE, AGM- 66  SELECT, UNCAGE, TRACK, BORESIGHT, FOY, AIRCRAFT IDENT, and TRACKING MODE. Analog input  46  also receives various input signals from the analog interface  32 . These signals include: AZ COMM AMO, EL COMM AMO, HORIZONTAL SLAVE and VERTICAL SLAVE. The above designated signals received from analog input  46  are sensed through comparators or analog inputs and converted to digital signals. Once the signals are converted to digital, the signals may be placed on the digital input/output bus  38  at the desired time for use as needed. 
   During analog operation (i.e., when the aircraft  10  is connected to the analog interface  32 ), the dual mode launcher assembly  30  is capable of transmitting various information received from the store  20  (through the digital input/output bus  38 ) to the to the aircraft  10  via the analog interface  32 . In particular, discrete output  42  transmits the following signals to the aircraft  10 : LAUNCHER PRESENT, AGM- 65  and MISSILE READY. Likewise, analog output  44  outputs the following information to the aircraft  10  via the analog bus  32 : ADAPTER EXCITATION (+), ADAPTER EXCITATION (−), EL GIMBAL ANGLE, and AZ GIMBAL ANGLE. Depending on the signal, the signals transmitted from the discrete output  42  and analog output  44  to the analog interface  32  will be synthesized through solid state relays and converted to analog by digital to analog (D/A) circuits controlled and monitored by the onboard microcontroller (not shown). In the analog mode, operation of the dual mode launcher assembly  30  is transparent to the user, but will be controlled internally by software rather than relays and discrete logic. 
   As shown in  FIGS. 2A and 2B , the analog interface  32  further transmits inputs for 115 V AC and 28 V DC to the box designated TO ZONE E 2   48 . In addition, the analog interface  32  further receives a VIDEO signal from TO ZONE E 2   48 . These signals are illustrated to clarify that the designated inputs are maintained on the analog interface  32  (i.e., the analog interface  32  includes power signals (e.g., 115 V AC and 28 V DC) and video signals (e.g., VIDEO). Thus, dual mode launcher assembly  30  permits users of legacy aircraft to maintain the full capabilities of a conventional legacy launcher. 
   Operation of the dual mode launcher assembly  30  in digital mode will now be discussed. For operations in the digital mode, the aircraft  10  must generally be compliant with MIL-STD-1760. Communications associated with the digital mode occur through digital interface  34  and store interface  36 . Generally, during operation in digital mode, all inputs from the store will be sensed through comparators or analog inputs (A/D), and all outputs to the missile will be synthesized through solid state relays and analog output (D/A) circuits controlled and monitored by the onboard microcontroller (not shown). 
   All inputs from the aircraft  10  are transmitted to dual mode launcher assembly  30  via MIL-STD-1553 digital data receive type messages. The bits in these messages generally have a one-to-one correspondence to the signals of the legacy interface. For example, a TRUE state on an analog discrete line will be handled by the launcher services processor (LSP)  92  (shown in  FIG. 3 ) software exactly the same way as a logical “1” for the corresponding bit in the MIL-STD-1553 data word. Likewise, outputs to the aircraft  10  will be via MIL-STD-1553 digital data transmit type messages. The data contained in these messages will correspond to the information normally available over the legacy interface. 
   As shown in  FIGS. 2A and 2B , digital data transmitted from the aircraft  10  to the dual mode launcher assembly  30  is received by Launcher RT  60  through redundant signal lines MUX A and MUX B. Launcher RT  60  is a two-way bus that receives various signals, including MUX A, MUXB and A 0 –A 4  F. The Launcher RT  60  is capable of receiving information from the aircraft  10 , and transmitting information to the aircraft  10 . The actual digital data received and transmitted by the launcher RT  60  is represented by the MUX A and MUX B signals. The A 0 –A 4  F signal essentially provides addressing information to the Launcher RT  60 . In turn, the Launcher RT  60  performs impedance matching to ensure that the digital data has the proper amplitude. Once synthesized, the MUX A and MUX B data are placed on the input/output bus  38  for use as needed. 
   As shown in  FIGS. 2A and 2B , 1760 Power  62  receives the following standardized power signals as set forth in MIL-STD-1760: REL CON, 28 VDC #2, and VDC #1 from the digital interface  34 . Two signals are output from the 1760 Power  62 . One signal is directed to switch  78  and the other signal is transmitted to the junction  63 . The output of switch  78  is input to Safety Critical Function  76  to ensure a redundant power is received at the Safety Critical Function  76 . The output of junction  63  is made available to the store  20  through the store interface  36 . 
   Switch  64  receives a 115 V AC signal from the digital interface  34 . Switch  64  also receives a 115 V AC signal From Zone E 8   68 . Switch  64  determines which type of aircraft the launcher dual mode launcher assembly  30  is connected. If switch  64  does not receive a signal called “Power Reset” (not shown), switch  64  will determine that the aircraft  10  is analog. This is done by detecting a 115 V AC originating from the analog interface  32 . If it is determined that the aircraft is analog, 115 V AC signal is disconnected from the connector associated with the digital interface  34 . 
   Safety Critical Discrete Output Section  88  is connected to the digital input/output bus  38 . The Safety Critical Discrete Output Section  88  receives commands from the aircraft and, if appropriate, transmits the following signals to the Safety Critical Functions  76 : LAUNCH, SECOND POWER CTRL, BATTERY CONTROL, ROCKET MOTOR CTRL. Once these signals are transmitted to the Safety Critical Functions  76 , if all the prerequisites are satisfied, a signal to the BATTERY and IGNITER are transmitted to the store  20  through store interface  36  for ignition of the store  20 . As shown in  FIGS. 2A and 2B , Safety Critical Discrete Output Section  88  further outputs a “DOME” signal to the store interface  36 . 
   Video Amp  66  transmits video from the store interface  36  to the digital interface  34 . As discussed more fully below, the video amp  66  is capable of receiving legacy video signals and converting those signals to RS-170 video signals in real time for display to the user on a cockpit display. The video amp  66  provides an input to FROM ZONE E 8   68 . If the output of box  68  is 115 V AC, the aircraft  10  is analog (as discussed above), otherwise, if the output of box  68  is 28 V DC, then the aircraft  10  is digital. If the aircraft  10  is analog, power supplied to switch  70  may be selectively routed to XFRMR  72 , DC Power Supplies  74  to the store interface  36 . 
   Finally, an interlock  58  is shown in  FIGS. 2A and 2B . The interlock  58  monitors the mated status of the connectors associated with the digital interface  34 . 
   The signals received and transmitted by the store interface  36  will now be discussed. From analog output  82  a variety of signals, including HORIZ SLEW/SLAVE, VERT SLEW/SLAVE, HORIZ SLAVE/DATA, VERT SLAVE/CLOCK, B-AXIS BIAS, C-AXIS BIAS and WARHEAD DELAY are transmitted to store bus  36 . Likewise, the following signals are transmitted to the store bus  36  through discrete output  84 : MISSILE ACTIVATE, TRACK COMMAND, TRACK MODE SELECT, POLARITY SELECT, ALIGN COMMAND, SLAVE COMMAND, ROTATION RIGHT, ROTATION LEFT, and MISSILE SEP. 
   Furthermore, an analog return signal  81 , which is connected to analog input section  2   80  and analog output section  2  exchanges information between the store interface  36  and the analog interface  32 . 
   As discussed above, the store interface  36  also receives the following signals from the Safety Critical boxes  88  and  76 : DOME, BATTERY, and IGNITER. In addition, a 28 V DC power signal from junction  63  or switch  64  may also be received by the store interface  34  depending on the operation mode (analog or digital). Likewise, a ±30 V DC signal is received from DC Power Supplies  74  and a 26 V AC signal is received from the XFRMR  72 . A discrete return signal  85  is also connected to discrete output section  84  and discrete input section  86  and connects directly to store interface  85 . 
   The store interface  36  is capable of receiving information from the store  20  and transmit the information to the active analog interface  32  and/or digital information  34 . In particular, the store interface  36  transmits B-AXIS GIMBAL ANGLE and C-AXIS GIMBAL ANGLE signals to analog input  80 . Likewise, the store interface  36  transmits MISSILE PRESENT, MISSILE IDENT, TGM IDENT, and SECOND PWR TRUE signals to discrete input  86 . The store interface  36  also transmits the LV RETURN signal to DC Power Supplies  74  and VIDEO signal to Video Amp  66 . 
   In the digital mode, there are several advanced features available for operating the dual mode launcher assembly  30 , which are generally not available during analog operation.
         1. Real time built-in-test (BIT) feedback: results of the launcher periodic built in test (PBIT) operations are available over the 1553 data bus. BIT results are also recorded in the dual mode launcher assembly  30  (even for legacy mode operation) and are available for post mission download using the MIL-STD-1760 mass data transfer protocol.   2. Enhanced data from the missile: information about the internal state of the missile is displayed as bar coded data on the video display is available for some Maverick variants. The dual mode launcher assembly  30  will decode this data and have it available over the 1553 data bus to provide real time feedback to the operator regarding the quality of specific missile operations.   3. Mission data recording: the bar coded data, even if not used by the aircraft  10 , will be recorded into dual mode launcher assembly  30  memory (not shown) using a five (5) second circular buffer. Post mission download of this data will be available using the MIL-STD-1760 mass data transfer protocol.   4. Launcher software update: launcher software can be updated in the field using standard MIL-STD-1760 test equipment.   5. RS-170 compliant video: the dual mode launcher assembly  30  will convert the Maverick video, frame by frame, into a video signal that is compliant with the RS-170 standard. Up to 16 frames of video will be stored for upload (via MIL-STD-1553) or video display.
 
Thus, while it is important to maintain backward compatibility with analog aircraft, the present invention provides additional benefits available through implementation of the MIL-STD-1760 standard.
       

   Referring to  FIG. 3 , the physical architecture of the dual mode launcher assembly  30  is shown in block diagram form. The dual mode launcher assembly  30  includes a launcher input board (LIB)  90 , launcher services processor (LSP)  92  and launcher output board (LOB)  94 . 
   The LIB  90  is the primary interface from inputs originating from both the legacy aircraft interface (identified by J 1 ) and the store  20  to dual mode launcher assembly  30  interface (J 2 ). In particular, the LIB  90  performs the following functions: 1) converts the 28 V direct current signal into a +5 DC signal and a +/−15 V DC signal for use by the three dual mode launcher assembly circuit boards ( 90 ,  92 , and  94 ), as shown in  FIG. 3 ; 2) translates the analog levels presented over the legacy aircraft and missile interfaces into logical TRUE/FALSE data entities that can be interpreted by the LSP  92 ; 3) autonomously collects and buffers the logic level input data for use by the LSP  92 ; 4) converts the analog gimbal angle signal, slew commands, slave commands, and warhead fuze delay signals to 12 bit digital signals for use by the LSP  92 ; and 5) creates an internal, protected, “Release Power” source from either the analog interface  32  or the digital interface  34 , identified on  FIGS. 2A and 2B . 
   The launcher output board (LOB)  94  is the primary interface for outputs coming from the dual mode launcher assembly  30  to both the analog interface  32  and store interface  36 . In particular, the LOB  94  translates logical TRUE/FALSE data entities furnished by the LSP  92  into analog levels that can be understood over the legacy aircraft and store interfaces  32 ,  36 . The LOB  94  further converts the 12-bit digital signals provided by the LSP  92  into the analog gimbal angle, slew commands, slave commands and warhead fuze delay signals. In addition, the LOB  94  uses the internal, protected, “Release Power” source to initiate the launch sequence when all prerequisites are met. 
   The LSP  92  controls the functionality of the dual mode launcher assembly  30 . For example, if the store  20  is a Maverick missile, the LSP  92  controls all dual mode launcher assembly  30  functions and the Maverick signal set manipulations. In particular, the LSP  92  controls the following functions: 1) determines one of three operating modes, analog mode, digital mode, or memory loader/verifier mode; 2) monitors the state of aircraft  10  power via the LIB  90 ; 3) monitors the state of aircraft input discretes  40  (shown in  FIGS. 2A and 2B ) (either via 1553 message or from LIB  90 ); 4) monitors the state of store input discretes  86  via LIB  90 ; runs internal state machine that mimics the operation of the analog interface (e.g., LAU-117A(V)3/A); 5) drives the state of aircraft output discretes  42  (either via 1553 message or from output board  94 ; 6) monitors the current state of the dual mode launcher assembly  30 ; 7) autonomously monitors and summarizes key weapon status information (e.g., video Bar Code information); and 8) provides built-in-test and error reporting. 
   The LSP  92  includes four (4) major subsystems: a microcontroller; a MIL-STD-1553 RT communications device; a timer and interrupt controller; and video interface. These subsystems work together under the discretion of the computer software configuration item to accomplish all of the communication, control, and monitoring functions required within the dual mode launcher assembly  30 . 
   The microcontroller is preferably a Motorola MPC-555 microcontroller with one board dual Controller Area Network (CAN) controllers, 26 KB of internal static RAM and 448 KB of flash memory. The microcontroller controls all operations within the dual mode launcher assembly  30  according to the dual mode launcher assembly  30  CSCI and the communications protocol. 
   The MIL-STD-1553 RT communications device includes a controller and a random access memory section that is shared with the MPC-555 microcontroller. The MIL-STD-1553 RT communications device communicates with the aircraft  10  and handles all message traffic to and from the aircraft  10  to the signal set control and monitoring functions associated with the store  20 . 
   The timer and interrupt controller function generates a periodic interrupt to maintain information about the current state of the dual mode launcher assembly  30  and all weaponry carried thereon, including one or more stores  20 . The timer and interrupt controller function also provides interrupts that signal the receipt of aircraft messages into the receiver/transmit data signals of the LSP  92 , internal communication errors, and a watchdog timer function. These interrupt signals form the basic backbone from the dual mode launcher assembly  30  communication functions. 
   The video interface function converts the native video signals of the legacy store coverts the native store video into an RS-170 compliant signal for use over the MIL-STD-1760 HB3 interface. In addition, the video interface function decodes store  20  information available in the bar code for use over the MIL-STD-1760 HB3 interface and also transmits the extracted information to a circular data recorder for post-mission data analysis. The video interface function maintains a separate video processor digital circuitry, which provides an added benefit that there is only a small amount of software or performance loading occurring on the microcontroller. 
   In addition, the LSP  92  has built in recording capability, which allows provides the ability of the dual mode launcher assembly  30  to record all of the information available at the store  20 , as well as the aircraft  10 , including status, control information, and video information. This feature enables a complete review of the flight, up until the point of store  20  release, and can be downloaded from the dual mode launcher assembly  30  and reviewed during debriefing when desired. 
   In operation, the firmware associated with the dual mode launcher assembly  30  utilizes an initialization process that sets up all of the initial conditions for operation. This includes configuration of the LSP  92  RAM, timers, and interrupt controller. All legacy outputs are initialized to an all off (“safe”) state. The MIL-STD-1553 RT device is initialized to communicate with the aircraft. If it is determined that there is no MIL-STD-1760 interface connected (i.e., all address lines are open), the LSP  92  will operate in legacy mode. All launcher monitor messages are initialized to an off (“safe”) state. 
   The dual mode launcher assembly  30  operates as a controller for weapons carried on the Maverick Launch Assembly. All functions remain under the control of the host aircraft SMS. The dual mode launcher assembly  30  receives MIL-STD-1553 messages from the aircraft and then acts upon these messages in accordance with the requirements of Maverick Launcher Interface Description Document (IDD), which defines specific control and monitoring message protocols. The IDD includes the dual mode launcher assembly  30  specific messages identified in Table 1. 
   
     
       
             
           
             
             
             
             
           
             
             
             
             
           
         
             
               TABLE 1 
             
           
           
             
                 
             
             
               Dual Mode Launcher Messages 
             
           
        
         
             
                 
                 
               DW 
                 
             
             
               Message Name 
               Subaddr. 
               Count 
               Description 
             
             
                 
             
           
        
         
             
               Aircraft ID/Store 
                1R 
               5 
               Provides launcher host aircraft 
             
             
               Location 
                 
                 
               and location information. 
             
             
               Store Description 
                1T 
               30 
               Provides Maverick System store 
             
             
                 
                 
                 
               identification and configuration 
             
             
                 
                 
                 
               to the host aircraft. 
             
             
               Launcher Control 
               10R 
               12 
               Provides capability to control 
             
             
               (LCM) 
                 
                 
               functions of the dual mode 
             
             
                 
                 
                 
               launcher assembly. 
             
             
               Launcher Monitor 
               10T 
               12 
               Provides capability to monitor 
             
             
               (LMM) 
                 
                 
               the status of the dual mode 
             
             
                 
                 
                 
               launcher assembly and carried 
             
             
                 
                 
                 
               weapon. 
             
             
               Launcher Store 
               11R 
               30 
               Provides the MIL-STD-1760 
             
             
               Control (LSC) 
                 
                 
               compliant message required to 
             
             
                 
                 
                 
               initiate launch. 
             
             
               Launcher Store 
               11T 
               30 
               Provides the MIL-STD-1760 
             
             
               Monitor (LSM) 
                 
                 
               compliant message required to 
             
             
                 
                 
                 
               monitor launch. 
             
             
               Transfer Data 
               13R/T 
               30 
               Required for MDT. 
             
             
               Transfer Control 
               14R 
               8 
               Required for MDT. 
             
             
               Transfer Monitor 
               14T 
               9 
               Required for MDT. 
             
             
               Data Wraparound 
               30R/T 
               30 
               Provides closed-loop data trans- 
             
             
                 
                 
                 
               fer integrity verification test. 
             
             
                 
             
           
        
       
     
   
   After initialization, dual mode launcher assembly  30  LSP software begins a main process that simply waits for commands from the aircraft, continuously assess the health (PBIT) and service the internal interrupts. Three interrupt driven processes are utilized within the dual mode launcher assembly  30  LSP  92 . That is, each process is only invoked when the specific event which the process is designed to handle does occur. 
   A receive/transmit interrupt process is responsible for handling each message received in the RT LSP  2  from the aircraft  10 . Each time a message is received from the aircraft  10 , this process is invoked to check for errors and to handle the message according to the communications protocol. The process handles all aspects of the message from verifying the message validity to setting the state of internal variables based on the content of the control message. 
   A timer interrupt process is initiated every 10 ms while power is applied to the dual mode launcher assembly  30 . The primary responsibility of the timer interrupt process is to generate the correct launcher responses to inputs over either aircraft interface  32 ,  34 . An internal state machine is updated during this process to handle the transitions from current state to next state based on inputs from the aircraft  10 , inputs from the store  20 , and internal status and timing signals. For example, the following signals are updated every 10 ms: 1) analog and discrete outputs to the store; 2) analog and discrete inputs from the store; 3) analog and discrete inputs from the aircraft (only if in legacy mode); 4) analog and discrete outputs to the aircraft (only if in legacy mode); 5) outputs to the igniter assembly (during launch sequence); and 6) internal status and BIT results. 
   The timer interrupt process is also responsible for generating a current LMM message every 10 ms. This process assembles a LMM with the current state of all of the internal data entities. The process places this message into the LSP  92  RT hybrid&#39;s shared RAM so that when the aircraft  10  commands the dual mode launcher assembly  30  to send a LMM message, the most current status information will be available. 
   The dual mode launcher assembly  30  further provides a watchdog timer. The watchdog timer will timeout, signifying a firmware or processor problem and setting the subsystem flag and processor non-maskable interrupt (NMI), if it is not reset at least every 1.6 seconds. Firmware is designed to reset the watchdog timer during each 10 ms status update. Execution of the NMI routine will log the fault, save all outputs and halt all further processing until power is removed and then re-applied to the dual mode launcher assembly  30 . 
   Although the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims.