Patent Publication Number: US-7710442-B2

Title: Two-sided thermal print configurations

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims priority to U.S. Provisional Application No. 60/779,781 entitled “Two-Sided Thermal Printing” and filed on Mar. 7, 2006 and U.S. Provisional Application No. 60/779,782 entitled “Dual-Sided Thermal Printer” and filed on Mar. 7, 2006, and is a continuation-in-part of U.S. application Ser. No. 11/644,262 entitled “Two-Sided Thermal Print Sensing” and filed on Dec. 22, 2006 and U.S. application Ser. No. 11/675,649 entitled “Two-Sided Thermal Print Switch” and filed on Feb. 16, 2007; the disclosures of which are hereby incorporated by reference herein. 

   BACKGROUND 
   Two, or dual-sided direct thermal printing of documents such as transaction documents and receipts is described in U.S. Pat. Nos. 6,784,906 and 6,759,366. In dual-sided direct thermal printing, the printers are configured to allow concurrent printing on both sides of thermal media moving along a feed path through the printer. In such printers a direct thermal print head is disposed on each side of the media along the feed path. In operation each thermal print head faces an opposing platen across the media from the respective print head. 
   In direct thermal printing, a print head selectively applies heat to paper or other sheet media comprising a substrate with a thermally sensitive coating. The coating changes color when heat is applied, by which “printing” is provided on the coated substrate. For dual-sided direct thermal printing, the sheet media substrate may be coated on both sides. 
   SUMMARY 
   A dual-sided direct thermal printer is provided for printing on both sides of a receipt, document, label or other thermal media moving along a feed path through the printer. In one embodiment, a dual-sided direct thermal printer comprises a first thermal print head on a first side of a media feed path, and a second thermal print head on a second side of the media feed path, wherein a surface associated with the first thermal print head acts as a platen for the second thermal print head. In various embodiments, one or more additional surfaces and/or rollers may be provided for use as a platen for a first and/or a second thermal print head, to guide, including turn or otherwise rotate, thermal media in the printer, and/or to transport thermal media through the printer. 
   Dual-sided direct thermal printing provides for printing of variable information on both sides of a print media, such as a receipt, to save materials, and to provide flexibility in providing information to customers. Dual-sided direct thermal printing can be driven electronically or by computer using a computer application program which directs dual-sided printing. Dual-sided printer functionality, may be controlled by, inter alia, a dual-sided print function switch using commands implemented with, for example, setup configuration settings in hardware or software, escape sequences, real-time printer commands, and the like. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1A  provides a schematic of a dual-sided imaging direct thermal printer useable for dual-sided printing of thermal media. 
       FIG. 1B  illustrates detail of a first example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2A  illustrates a second example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2B  illustrates a third example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2C  illustrates a fourth example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2D  illustrates a fifth example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2E  illustrates a sixth example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2F  illustrates a seventh example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 2G  illustrates an eighth example print head and platen configuration for use with a dual-sided imaging direct thermal printer. 
       FIG. 3A  shows a two-sided receipt with transaction detail printed on the front side. 
       FIG. 3B  shows the receipt of  FIG. 3A  with supplemental information printed on the reverse side, such as variable stored information selected on the basis of the transaction detail. 
       FIG. 3C  shows a two-sided receipt with a portion of the associated transaction detail printed on the front side of the receipt. 
       FIG. 3D  shows the reverse side of the receipt of  FIG. 3C  on which the remaining portion of the associated transaction data is printed. 
       FIG. 4  shows a perspective view of an exemplary dual-sided direct thermal receipt printer for retail Point of Sale (POS) application. 
       FIG. 5  schematically shows a partial centerline cross-sectional view of the dual-sided direct thermal receipt printer of  FIG. 4 . 
       FIG. 6  schematically shows a partial gear plane cross-sectional view of the dual-sided direct thermal receipt printer of  FIG. 4 . 
       FIG. 7  schematically shows a partial centerline cross-sectional view of the dual-sided direct thermal receipt printer of  FIG. 4 , with a cover in an open position. 
       FIG. 8  schematically shows a partial centerline cross-sectional view of a variation of the dual-sided direct thermal receipt printer of  FIG. 4 . 
       FIG. 9  schematically shows a partial gear plane cross-sectional view of the dual-sided direct thermal receipt printer of  FIG. 8 . 
       FIG. 10  schematically shows a partial centerline cross-sectional view of a variation of the dual-sided direct thermal receipt printer of  FIG. 4 . 
       FIG. 11  schematically shows a partial gear plane cross-sectional view of the dual-sided direct thermal receipt printer of  FIG. 10 . 
       FIG. 12  schematically shows a partial centerline cross-sectional view of a further variation of the dual-sided direct thermal receipt printer of  FIG. 4 . 
       FIG. 13  schematically shows a further variation in a dual-sided direct thermal printer print head and platen orientation, and media feed path. 
       FIG. 14  schematically shows a further variation in a dual-sided direct thermal printer print head and platen orientation, and media feed path. 
   

   DETAILED DESCRIPTION 
   By way of example, various embodiments of the invention are described in the material to follow with reference to the included drawings. Variations may be adopted. 
     FIG. 1A  illustrates a schematic of a dual-sided imaging direct thermal printer  10  useable for, for example, dual-sided printing of documents, such as transaction receipts or tickets, at time of issue. The printer  10  operates on print media  20  comprising, for example, double-sided thermal paper which paper may comprise a cellulosic or polymer substrate sheet coated on each side with heat sensitive dyes as described in U.S. Pat. Nos. 6,784,906 and 6,759,366 the contents of which are hereby incorporated herein by reference. 
   Dual-sided direct thermal printing can be facilitated by, for example, a media  20  which includes dyes on opposite sides of the media  20 , and a sufficiently thermally resistant substrate to inhibit thermal printing on one side of the media  20  from affecting coloration on the opposite side of the media  20 . Such thermal print media  20  may be supplied in the form of a roll, fan-fold stack, individual sheet and the like, upon which printing such as graphics or text, or both, may be printed on one or both sides of the media  20  by a dual-sided imaging direct thermal printer  10 , to provide, for example, a voucher, coupon, receipt, ticket or other article or document. 
   As shown in  FIG. 1A , a dual-sided imaging direct thermal printer  10  may include platens  30  and  40  and opposing thermal print heads  50  and  60  on opposite sides of a media feed path  25  for printing on opposite sides of thermal media  20 , although alternate print head and platen designs and/or configurations are possible. In addition, a dual-sided imaging direct thermal printer  10  may include a media drive system  12  for moving media  20  through the printer  10  during a print process. Media drive system  12  may comprise one or more motors (not shown) for powering a system of gears, links, cams, belts, pulleys, combinations thereof, and the like, during operation of the dual-sided printer  10 . In one embodiment, one or more platens  30  and  40  provided in the form of circular cylinders are rotated by a drive assembly  12  in order to move the print media  20  through the dual-sided printer  10 , although additional drive means, including the use of one or more additional, dedicated drive rollers (not shown), are also possible. 
   In further reference to  FIG. 1A , a dual-sided imaging direct thermal printer  10  may also include first and second support arms  14  and  16 . Second support arm  16  may further be journaled on an arm shaft  18  to permit the second support arm  16  to pivot or rotate in relation to the first support arm  14  to, for example, facilitate access to, and servicing of, the dual-sided printer  10 . In alternate embodiments, the support arms  14  and  16  may be in a fixed relation to one another. As shown in the embodiment of  FIG. 1A , a first platen  30  and a first thermal print head  60  may be coupled to or formed integrally with a first support arm  14 , while a second platen  40  and a second thermal print head  50  may be coupled to or formed integrally with a second support arm  16 . Alternatively, a first platen  30  and a second thermal print head  50  may be coupled to or formed integrally with a first support arm  14 , while a second platen  40  and a first thermal print head  60  may be coupled to or formed integrally with a second arm  16 . Variations in such component design and/or configuration, including printer  10  designs where a first platen  30  and a first and a second thermal print head  50  and  60  are coupled to or formed integrally with a first arm  14  while a second platen  40  is coupled to or formed integrally with a second support arm  16 , or a first and a second platen  30  and  40 , and a first and a second thermal print head  50  and  60  are coupled to or formed integrally with a first arm  14 , and the like, are also possible. 
   In operation, dual-sided direct thermal printing of media  20  by a dual-sided imaging direct thermal printer  10  may occur in a single pass of the media  20  through the printer  10  at, for example, completion of a transaction such as when a receipt or ticket is issued. Alternately, dual-sided direct thermal printing may occur in a two or more pass process where, for example, the media  20  is imaged by one or both thermal print heads  50  and  60  when moving in a first direction, and then retracted for further imaging by one or both thermal print heads  50  and  60  with the media moving in either the first or the second, retract direction. Once printing is completed the media  20  may, depending on its format (e.g., roll, fan fold, individual sheets, and the like), be manually or automatically cut or severed to provide an individual receipt, ticket, or other document. 
   As shown in  FIG. 1A , a dual-sided imaging direct thermal printer  10  may further include a switch  70  enabling, inter alia, activation and/or deactivation of one or more dual-sided printing modes or functions. Such dual-sided printing function switch  70  may be a mechanically operated switch associated with the printer  10 , or an electronically operated switch operated by, for example, a printer driver on an associated host computer or by firmware or software resident on the printer  10 , and the like. In one embodiment, a printing function switch  70  may be electronically operated in response to a command message or escape sequence transmitted to the printer  10  through use of, for example, a communication controller  96 . Communication controller  96  may communicate with one or more host or auxiliary systems such as a point-of-sale (POS) terminal (not shown), an automated teller machine (ATM) (not shown), a self-service kiosk (not shown), a self-checkout system (not shown), a personal computer (not shown), and the like, for input of data to, and output of data from, the printer  10 . Communication controller  96  may support one or more communication protocols such as parallel, USB, RS232, RS485, Ethernet and/or wireless communications (e.g., 802.11, 802.15, and IR), among others. In communicating with the printer  10  printer control language or printer job language (“PCL/PJL”), or escape commands, and the like, may be used. A printer setup configuration program setting, e.g., a setting made through a software controlled utility page implemented on an associated host computer, may also be used to electronically operate a function switch  70  for a dual-sided imaging direct thermal printer  10 . 
   In one embodiment, a dual-sided printing function switch  70  may be configured, programmed or otherwise setup to select or otherwise identify, inter alia, (1) data for printing (e.g., internally stored macros, externally received transaction data, and the like), (2) which of the provided thermal print heads  50  and  60  will be used to print and/or be used to print particular data, (3) whether selected data will be printed when the media  20  is moving in a first (e.g., forward) or second (e.g., backward) direction, (4) in which relative and/or absolute media location, including on which media side, particular data will be printed, (5) in which orientation (e.g., rightside-up, upside-down, angled, and the like) particular data will be printed on the media  20 , and the like. For example, a setting of the dual-sided printing function switch  70  may marshal a portion (e.g., a first half) of a block of selected externally received and/or internally stored print data to be printed on a first (e.g., front) side of the media  20  and another portion (e.g., a second half) to be printed on a second (e.g., reverse) side of the media  20 . A further setting may reverse the media sides on which the respective portions of data are to be printed. In this manner a document such as a transaction receipt may be generated in which a portion of the associated transaction data is printed on one side of the receipt and the remaining portion of the transaction data is printed on the other side of the receipt, conserving upon the amount of media  20  required for printing of the receipt. A dual-sided printing function switch  70  may accordingly be configured, e.g., by a control or other command message manually set at or otherwise transmitted to the printer  10 , to determine, inter alia, a portion, quantity or block of data to be printed on each side of the media  20 . Different blocks of data, or portions thereof, may be selected and marshaled to different sides, or locations thereon, of the media  20  by the switch  70 . 
   In one embodiment, a printing function switch  70  may select a first portion of print data for printing on a first side of thermal media  20 , such as a receipt paper roll, and a second portion of print data for printing on a second side of the thermal media  20 . Such print data may comprise data contemporaneously received by the printer  10  from a host computer such as a point-of-sale (POS) terminal (not shown), an automated teller machine (ATM) (not shown), a self-checkout system (not shown), a personal computer (not shown), and the like, and/or data previously stored in one or more memory or buffer locations  80  in the printer  10 . It should be noted that print data may be (1) processed for printing before receipt by or storage in the printer  10  by, for example, a host computer such as a POS terminal, (2) processed for printing after receipt by or storage in the printer  10  by, for example, the printing function switch  70 , or a controller or processor  90  associated with the printer  10 , or (3) a combination of (1) and (2), among others. Likewise, such processing may occur before or after selection, identification and/or apportionment of the print data for printing on the first and/or second side of thermal media  20  by the printing function switch  70 . 
   In another embodiment, a printing function switch  70  may be configured to select or otherwise identify print data for printing at a specified location, including a side, of the print media  20  based upon a quantity of media required to print such data. Such quantity may be determined based on, inter alia, (1) a physical, as-printed size (e.g., length, width, perimeter, area, font size, and the like) of the to-be-printed data, (2) a portion of the media  20  that is thermally imageable (e.g., a portion having one or more thermally sensitive coatings), (3) a portion of the media  20  which is pre-printed or pre-imaged, (4) a portion of the media  20  which is excluded or desired to be excluded from thermal or other imaging (e.g., margins, headers, line spacings, indentations, desired or required blank space, and the like), (5) physical characteristics of the printer  10  (e.g., size of the platens  30  and  40 , size of the thermal print heads  50  and  60 , spacing of the platens  30  and  40 , spacing of the thermal print heads  50  and  60 , length of a media feed path  25  between the thermal print heads  50  and  60 , and the like), and the like. 
   In one embodiment, a printing function switch  70  may apportion a first portion of print data for printing on a first side of media  20  and a second portion of print data for printing on a second side of the media  20 , wherein the first and second portions are selected to occupy substantially the same amount of space on the respective first and second media sides when printed. Likewise, the printing function switch  70  may apportion a first portion of print data for printing on a first side of the media  20  and a second portion of print data for printing on a second side of the media  20 , opposite the first side, wherein the as-printed size of the first portion is selected to be greater than the as-printed size of the second portion. Differences in the as-printed size of the first and second data portions may be selected to accommodate, inter alia, (1) differences in an amount of printable space (e.g., accounting for margins, headers, footers, preprinted information, thermal coating coverage, and the like) available on the first and the second sides of the media  20 , (2) differences in the type of data (e.g., internally stored macro data such as logos, coupons, advertisements, and the like, versus externally received transaction data such as purchased items, quantity, price, and the like) selected for printing on a given side, and (3) differences in print location on the first and the second sides of the media  20  by the thermal print heads  50  and  60  location. Differences in print location on the first and the second sides of the media  20  by the print heads  50  and  60  in a dual-sided imaging direct thermal printer  10  may arise from differences in vertical, horizontal and/or depthwise placement of the print heads  50  and  60  in the printer  10  which may result in, for example, imaging of a first side of thermal media  20  by a first thermal print head before imaging of a second side of the thermal media  20  by a second thermal print head when the media  20  is moving along the media feed path  25 . More specifically, differences in print location on the first and the second sides of the media  20  may arise from differences from a length of media  20  between a respective printing portion of the thermal print heads  50  and  60  along the media feed path  25  (e.g., following the arrow at the top of  FIG. 1A ) in the printer  10 , which may result from differences in location of the print heads  50  and  60 , as well as placement of other media contact surfaces, such as rollers, and the like, along the media feed path. 
   In one embodiment, the printing function switch  70  may apportion a first portion of print data, such as ticket information, for printing on a first side of the media  20  and a second portion of print data, such as a legal information, for printing on a second side of the media  20 , opposite the first side, wherein the as-printed size (e.g., printed area) of the first portion is selected to be greater than the as-printed size (e.g., printed area) of the second portion by an amount substantially equivalent to an amount of printable space (e.g., area) along the media feed path  25  on the second side of the media  20  between the thermal print heads  50  and  60 . It should be noted that the as-printed size of print data on a given media  20  side may be controlled by selection of an amount of data to be printed on a given side, selection of a size at which selected data is to be printed (e.g., font, font size, and/or data scaling), and the like. 
   In a further embodiment, first and second portions of data received by a printer  10 , such as POS transaction data, may be identified by a printing function switch  70  such that a length of a first side of print media  20 , such as a receipt, to be occupied by the first portion of the print data is greater than a length of a second side of the print media  20  to be occupied by the second portion of the print data by a length substantially equivalent to a length of media between the platens  30  and  40  and/or thermal print heads  50  and  60  along the media feed path  25 . Other relevant lengths and/or variations in the apportionment of print data are, of course, possible. Additionally, received print data may be stored in one or more buffers  80  of the printer  10  before or after identification by the printing function switch  70  for printing on one or both sides of the media  20 . 
   In another embodiment, data selected or otherwise identified for printing on one or both sides of media  20  by the printing function switch  70  may include predefined print data or macros, such as one or more of a location identifier (e.g., address), an establishment identifier (e.g., store), a computer identifier (e.g., POS terminal), a logo, an advertisement, and the like, stored in one or more memories  80  associated with the printer  10 . In one example, some or all of such predefined print data may be selected for printing on a portion of the media  20  along the media feed path  25  between the first and the second thermal print heads  50  and  60  on one or both sides of the media  20 . Further, such information may be selected for printing in advance of any contemporaneously received print data, such as transaction data received from a POS terminal, which is to be included on, for example, the same document or receipt. As such, predefined print data may be selected for printing on regions of the media  20  where it may otherwise be difficult or undesirable for printing of contemporaneous information to occur, such as a region of media  20  along the media feed path  25  between the first and second thermal print heads  50  and  60 , thereby maximizing use of the media  20 . 
   In a further embodiment, a printing function switch  70  may apportion print data, including internally stored macros and/or received transaction data, among a first and a second side of thermal media  20  in order to optimize use of the media. In performing such optimization, the printing function switch may control the as-printed size (e.g., font, font size, scaling, and the like) of selected print data. Likewise, the printing function switch  70  may take account of, inter alia, (1) media size and design parameters including desired or required headers, footers, margins, and the like, (2) thermally sensitive coating location(s), and (3) any information that may be preprinted on the media  20 . In one embodiment, such accounting may comprise the printing function switch  70  avoiding apportionment of some or all of the selected print data to certain media regions such as regions where preprinted data exists, apportioning of some or all of the selected print data to certain media regions such as regions set off by one or more sensemarks, and the like. In still further embodiments, one or more sensors  100 , such as one or more thermal and/or optical sensors, may be used to sense regions of preprinted information and/or regions demarked by one or more sensemarks for making apportionment and non-apportionment decisions as part of such print media use optimization. 
   Additionally or alternatively, one or more sensors  100  may be provided to ascertain a type (e.g., single-sided thermal, double-sided thermal, non-thermal, label, roll, fan-fold, cut sheet, preprinted, and the like), size (e.g., length, width, thickness, and the like), and quantity (e.g., weight, length, volume, and the like) of media  20  loaded into a printer  10 , as well as whether media is installed in the printer  10 . Signals from such sensors may then be used to, inter alia, assist in apportionment of data for printing on the media  20 , provide notification to an operator of the type, size and/or quantity of media  20  in the printer  10 , and/or enable and/or disable one or more functions of the printer  10  based on one or more signals from the one or more sensors  100 . Additional detail regarding the use of one or more sensors  100  to control operation of, or functionality provided by, a dual-sided imaging thermal printer  10  is provide in U.S. application Ser. No. 11/644,262 entitled “Two-Sided Thermal Print Sensing” and filed on Dec. 22, 2006, the disclosure of which is hereby incorporated by reference herein for all purposes. 
   In a further embodiment, apportionment of print data may be made by a printing function switch  70  such that a length of media  20  along a media feed path  25  to be occupied by print data on a first side of the media  20  differs from a length of the media  20  along the media feed path  25  to be occupied by print data on a second side of the media  20 , by a length substantially equivalent to a spacing between platens  30  and  40 , a length substantially equivalent to a spacing between the thermal print heads  50  and  60 , and/or a length of media between thermal print heads  50  and  60 , and/or thermally active portions thereof, along the media feed path  25 , and the like.  FIG. 1B  provides further detail of the platen  30  and  40  and thermal print head  50  and  60  configuration, including thermally active portions thereof, of  FIG. 1A . 
   In the configuration of  FIG. 1B  a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Likewise, a second platen  40  in the form of a circular cylinder is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along the media feed path  25 . As described with respect to  FIG. 1A , one or both platens  30  and  40 , and thermal print heads  50  and  60  may be further coupled to or formed integrally with one or more support arms  14  and  16  (not shown). 
   As further shown in  FIG. 1B , each of the thermal print heads  50  and  60  include a printing surface  52  and  62  comprising one or more thermal print elements  54  and  64 . Each of the one or more thermal print elements  54  and  64  may span some or all of the respective printing surfaces  52  and  62 , in a direction parallel and/or perpendicular to (e.g., normal to the page comprising  FIG. 1B ) the media feed path  25 . Where provided, one or more thermal print elements  54  and  64  may allow for simultaneous two-sided thermal printing across a portion of one or both sides of thermal media, such as a width of the thermal media perpendicular to the media feed path  25  and/or a length of thermal media parallel to the media feed path  25 , provide for application of multiple levels of heating for controlling imaging of installed thermal media, and the like. 
   In the print head and platen configuration of  FIG. 1B , movement of thermal media along the media feed path  25  may be provided for by coupling the first and/or the second platen  30  and  40  for rotation to a drive system  12  as described with respect to  FIG. 1A . Alternately or additionally, movement of thermal media along the media feed path  25  may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a drive system  12 . 
   While  FIG. 1B  provides detail of a single print head and platen configuration for use in a dual-sided imaging direct thermal printer  10  (e.g., a configuration according to  FIG. 1A ), it should be noted that variations in thermal print head and platen design and configuration are possible. In particular, multiple variations where one or more surfaces associated with one or more thermal print heads act as platens for one or more additional thermal print heads are possible.  FIG. 2A  illustrates one such print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  according to  FIG. 1A . 
     FIG. 2A  illustrates a second print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2A , a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . However, unlike  FIG. 1B , a second platen  40  is provided in the form of a portion of a printing surface  52  of the first thermal print head  50 . In  FIG. 2A , the second platen  40  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along a media feed path  25 . As previously described with respect to  FIG. 1A , one or more platens  30  and  40 , and thermal print heads  50  and  60  may be further coupled to or formed integrally with one or more support arms  14  and  16 . 
   As further shown in  FIG. 2A , each of the thermal print heads  50  and  60  include a printing surface  52  and  62  each comprising one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   Additionally, some or all of the printing surfaces  52  and  62  of the thermal print heads  50  and  60  may comprise one or more friction reducing materials  56  and  66  to facilitate motion of, and minimize damage to and/or from, thermal media along the media feed path  25 . Such friction reducing material may be provided as a discrete portion, layer or coating of a respective printing surfaces  52  and  62 . In one embodiment, a coating or layer of friction reducing material  56  and/or  66  such as polytetrafluoroethylene (PTFE), and/or electroless nickel incorporating PTFE (e.g., PTFE particles dispersed in an electroless nickel matrix), is applied to some or all of the printing surfaces  52  and  62  of the first and second thermal print heads  50  and  60 , although variations are possible. 
   Movement of thermal media along a media feed path  25  of  FIG. 2A  may be provided for by rotation of the first platen  30  by a drive system  12  as described with respect to  FIG. 1A . Likewise, movement of thermal media may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a separate and/or shared drive system  12 , alone or in combination with rotation of the first platen  30 , among other means. 
     FIG. 2B  illustrates a third print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2B , a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Further, in the configuration of  FIG. 2B , a second platen  40  is provided in the form of a portion of a surface associated with the first thermal print head  50 . As for  FIG. 2A , the second platen  40  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along a media feed path  25 . 
   As further illustrated in  FIG. 2B , each of the thermal print heads  50  and  60  include a printing surface  52  and  62  each of which may comprise one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   Additionally, some or all of the printing surfaces  52  and  62 , or other surfaces of the thermal print heads  50  and  60 , such as a surface comprising the second platen  40 , may comprise a friction reducing material  56  to facilitate motion of, and minimize damage to or from, thermal media moving along the media feed path  25 . Such friction reducing material may be provided as a discrete portion, layer or coating of a respective surface of the first or second thermal print heads  50  and  60 . In one embodiment, the friction reducing material  56  comprises a layer of polytetrafluoroethylene (PTFE) and/or electroless nickel incorporating PTFE applied to some or all of a surface of the first thermal print head  50  comprising the platen  40 , although other materials and locations are possible. 
   The configuration of  FIG. 2B  additionally includes a roller  72  to orient media for printing on opposite sides thereof by the first and the second thermal print heads  50  and  60 . Movement of thermal media along the media feed path  25  of  FIG. 2B  may be provided for by rotation of the first platen  30  and/or the roller  72  coupled to a drive system  12  as described with respect to  FIG. 1A , and/or it may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a drive system  12 . 
   Similarly, and as previously described with respect to  FIG. 1A , one or both platens  30  and  40 , and thermal print heads  50  and  60 , as well as a roller  72 , may be further coupled to or formed integrally with one or more support arms  14  and  16 . In one embodiment, a first platen  30  and second thermal print head  60  are coupled to or formed integrally with a first support arm  14  while a first thermal print head  50  and roller  72  are coupled to or formed integrally a second support arm  16 . 
     FIG. 2C  illustrates a fourth print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2C , a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Further, a second platen  40  is provided in the form of a portion of a surface associated with the first thermal print head  50 . In the configuration of  FIG. 2C , the second platen  40  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along the media feed path  25 . 
   As further shown in  FIG. 2C , each of the thermal print heads  50  and  60  include a printing surface  52  and  62  each of which comprises one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   Additionally, some or all of the printing surfaces  52  and  62 , or other surfaces of the thermal print heads  50  and  60 , such as some or all of a surface of the first thermal print head  50  comprising the second platen  40 , may comprise one or more friction reducing materials  56  and  66  to facilitate motion of, and minimize damage to or from, thermal media moving along the media feed path  25 . Such friction reducing materials may be provided as a discrete portion, layer or coating of, a respective surface of a first and/or second thermal print head  50  and  60 . In one embodiment, one or more friction reducing material  56  and  66  comprise one or more blocks of polytetrafluoroethylene (PTFE) and/or electroless nickel incorporating PTFE attached to some or all of a surface of a first thermal print head  50  comprising a platen  40 , and some or all of a printing surface  62  of a second thermal print head  60 , which may include a region associated with one or more print elements  64 , although other materials and locations are possible. 
   The configuration of  FIG. 2C  additionally includes a roller  72  to orient media for printing on opposite sides thereof by the first and the second thermal print heads  50  and  60 . Movement of thermal media along the media feed path  25  of  FIG. 2C  may be provided for by rotation of the first platen  30  and/or the roller  72  through use of a drive system  12  as described with respect to  FIG. 1A , and/or it may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a drive system  12 . 
   Likewise, and as previously described with respect to  FIG. 1A , one or both platens  30  and  40 , thermal print heads  50  and  60 , and/or roller  72 , may be further coupled to or formed integrally with one or more support arms  14  and  16 . In one embodiment, a first platen  30  and second thermal print head  60  are coupled to or formed integrally with a first support arm  14  while a first thermal print head  50  and roller  72  are coupled to or formed integrally with a second support arm  16 . 
     FIG. 2D  illustrates a fifth print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2D , a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Further, in the configuration of  FIG. 2D , a second platen  40  is provided in the form of a portion of a surface associated with the first thermal print head  50 . As shown, the second platen  40  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along a media feed path  25 . 
   As further illustrated in  FIG. 2D , each of the thermal print heads  50  and  60  include a printing surface  52  and  62  each of which comprises one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   Additionally, some or all of the printing surfaces  52  and  62 , or other surfaces of the thermal print heads  50  and  60 , such as a surface comprising the second platen  40 , may comprise a friction reducing material  56  to facilitate motion of, and minimize damage to or from, thermal media moving along the media feed path  25 . Such friction reducing material may be provided as a discrete portion, layer or coating of a respective surface of the first or second thermal print heads  50  and  60 . In one embodiment, a friction reducing material  56  comprises a layer of polytetrafluoroethylene (PTFE) and/or electroless nickel incorporating PTFE applied to some or all of a surface of the first thermal print head  50  comprising the platen  40 , although other materials and locations are possible. 
   The configuration of  FIG. 2D  additionally includes one or more rollers  72  to orient media for printing on opposite sides thereof by the first and the second thermal print heads  50  and  60 . In the embodiment of  FIG. 2D , use and orientation of one or more rollers  72  facilitates turning or other rotation of thermal media in two planes (nominally 270 degrees in one and ninety in another) to support printing on both sides thereof by the thermal print heads  50  and  60 . 
   Movement of thermal media along the media feed path  25  of  FIG. 2D  may be provided for by rotation of the first platen  30  and/or one or more rollers  72  coupled to a drive system  12  as described with respect to  FIG. 1A , and/or it may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a drive system  12 . 
   Similarly, and as previously described with respect to  FIG. 1A , one or both platens  30  and  40 , and thermal print heads  50  and  60 , as well as rollers  72 , may be further coupled to or formed integrally with one or more support arms  14  and  16 . In one embodiment, a first platen  30  and second thermal print head  60  may be coupled to or formed integrally with a first support arm  14  while a first thermal print head  50  and a roller  72  may be coupled to or formed integrally a second support arm  16 . 
     FIG. 2E  illustrates a sixth print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2E , a first platen  30  in the form of a portion of a printing surface  62  of a second thermal print head  60  is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Likewise, a second platen  40  in the form of a portion of a printing surface  52  of the first thermal print head  50  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along a media feed path  25 . 
   As further shown in  FIG. 2E , the printing surfaces  52  and  62  of the thermal print heads  50  and  60  may each comprise one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   As additionally shown in  FIG. 2E , some or all of the printing surfaces  52  and  62  of the thermal print heads  50  and  60 , may comprise one or more friction reducing materials  56  and  66  to facilitate motion of, and minimize damage to or from, thermal media along moving the media feed path  25 . Such friction reducing materials may be provided as a discrete portion, layer or coating of, a respective printing surface  52  and  62  of the first and/or second thermal print heads  50  and  60 . In one embodiment, friction reducing materials  56  and  66  may comprise a coating of polytetrafluoroethylene (PTFE) and/or electroless nickel incorporating PTFE applied to some or all of the printing surfaces  52  and  62  of the first and second thermal print heads  50  and  60 , although other materials and locations such as a location including some or all of the thermal print elements  54  and  64 , are possible. 
   The configuration of  FIG. 2E  may additionally include one or more rollers  72  and  74  to facilitate movement of thermal media along the media feed path  25 . Such movement may be facilitate by coupling one or both of the rollers  72  and  74  for rotation to a drive system  12 , as described with respect to  FIG. 1A , although alternate configurations and/or drive means are possible. 
   As previously described with respect to  FIG. 1A , one or both thermal print heads  50  and  60 , and associated platens  30  and  40 , with or without one or both rollers  72  and  74 , may be further coupled to or formed integrally with one or more support arms  14  and  16 . In one embodiment, a first thermal print head  50 , including an associated second platen  40 , and a first and a second roller  72  and  74  may be coupled to or formed integrally with a first support arm  14  while a second thermal print head  60 , including an associated first platen  30 , may be coupled to or formed integrally a second support arm  16 , although alternate configurations are possible. 
     FIG. 2F  illustrates a seventh print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2F , a first platen  30  in the form of a portion of a printing surface  62  associated with a second thermal print head  60  is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . Likewise, a second platen  40  in the form of a portion of a printing surface  52  of the first thermal print head  50  is provided proximate to a second thermal print head  60  to facilitate printing on a second side of thermal media transported along the media feed path  25 . 
   As further illustrated with respect to  FIG. 2F , the printing surfaces  52  and  62  of the thermal print heads  50  and  60  may comprise one or more thermal print elements  54  and  64  each. The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   As further shown in  FIG. 2F , the one or more print elements  54  and  64  of the first and the second thermal print heads  50  and  60  are substantially opposite each other across the media feed path  25  such that a region of the first thermal print head  50  comprising one or more print elements  54  acts as a second platen  40  for printing by the second thermal print head  60 , and a region of the second thermal print head  60  comprising one or more print elements  64  acts as a first platen  30  for printing by the first thermal print head  50 . 
   As additionally illustrated in  FIG. 2F , some or all of a printing surface  52  and  62  of a thermal print head  50  and  60 , may comprise one or more friction reducing materials  56  and  66  to facilitate motion of, and minimize damage to or from, thermal media moving along a media feed path  25 . Such friction reducing materials may be provided as, inter alia, a discrete portion, layer or coating of a respective printing surface  52  and  62  of the first and/or second thermal print heads  50  and  60 . In one embodiment, friction reducing materials  56  and  66  may comprise a block of polytetrafluoroethylene (PTFE) and/or electroless nickel incorporating PTFE affixed to some or all of a printing surface  52  and  62  of a first and a second thermal print head  50  and  60 , although other materials and locations such as a location including some or all of a thermal print element  54  and  64 , are possible. 
   As further shown in  FIG. 2F , one or more print head and platen configurations may additionally include one or more rollers  72  and  74  to facilitate movement of thermal media along a media feed path  25 . Such movement may be facilitate by coupling one or both of the rollers  72  and  74  for rotation to a drive system  12 , as described with respect to  FIG. 1A , although other configurations and drive means are possible. 
   As previously described with respect to  FIG. 1A , one or both thermal print heads  50  and  60 , and associated platens  30  and  40 , with or without one or both rollers  72  and  74 , may be further coupled to or formed integrally with one or more support arms  14  and  16 . In one embodiment, a first thermal print head  50 , including an associated second platen  40 , and a first roller  72  may be coupled to or formed integrally with a second support arm  16  while a second thermal print head  60 , including an associated first platen  30 , and a second roller  74  may be coupled to or formed integrally a first support arm  14 , although alternate configurations are possible. 
     FIG. 2G  illustrates an eighth print head and platen configuration for use with a dual-sided imaging direct thermal printer  10  such as that illustrated in  FIG. 1A . As shown in  FIG. 2G , a first platen  30  in the form of a circular cylinder is provided proximate to a first thermal print head  50  to facilitate printing on a first side of thermal media transported along a media feed path  25 . As further shown in  FIG. 2G , a second platen  40  in the form of a portion of a printing surface  52  of the first thermal print head  50  is provided to facilitate printing by a second thermal print head  60  on a second side of thermal media transported along the media feed path  25 . As previously described with respect to  FIG. 1A , one or more of the platens  30  and  40 , and the thermal print heads  50  and  60  may be further coupled to or formed integrally with one or more support arms  14  and  16 . 
   Each of the thermal print heads  50  and  60  of  FIG. 2G  include a printing surface  52  and  62  each comprising one or more thermal print elements  54  and  64 . The one or more thermal print elements  54  and  64  of a respective print head  50  and  60  may provide for printing across a portion of one or both sides of thermal media, such as a length, width or area of thermal media, provide for application of multiple heat levels for controlling imaging of installed thermal media, and the like. 
   Additionally, some or all of the printing surfaces  52  and  62  of the thermal print heads  50  and  60  may comprise one or more friction reducing materials, such as friction reducing material  56  associated with the printing surface  52  of the first thermal print head  50  illustrated in  FIG. 2G . In some embodiments, a friction reducing material in the form of a coating or block of polytetrafluoroethylene (PTFE), and/or electroless nickel incorporating PTFE (e.g., PTFE particles dispersed in an electroless nickel matrix), may be applied to some or all of the printing surfaces  52  and  62  of the first and second thermal print heads  50  and  60 , including some or all of the thermal print elements  54  and  64 , although variations are possible. 
   Movement of thermal media along the media feed path  25  of  FIG. 2G  may be provided for by rotation of the first platen  30  by a drive system  12  as described with respect to, inter alia,  FIG. 1A . Likewise, movement of thermal media may be provided for through use of separate drive means, such as one or more separate drive rollers (not shown), coupled for rotation to a separate and/or shared drive system  12 , alone or in combination with rotation of the first platen  30 , among other means. 
   The print head and platen configuration of  FIG. 2G  is similar to the print head and platen configuration of  FIG. 2A  with the second thermal print head  60  of  FIG. 2G  being provided in the form of an edge type thermal print head. In that regard, it should be noted that any of the thermal print heads  50  and/or  60  of  FIGS. 1A-1B  and  2 A- 2 F, and print heads  210  and/or  270  of  FIG. 5-7 , among others, may be flat (e.g., plate) type, edge type, corner-edge type, or any other type or shape thermal print head suitable for use in a direct thermal printer such as the dual-sided imaging direct thermal printer  10  of  FIG. 1A . 
   Control of heat output by a thermal print head, such as a thermal print head  50  or  60  of  FIGS. 1A-1B  and  2 A- 2 G, including control of heat output by particular print elements, such as print elements  54  and  64  of  FIGS. 1B through 2G , may be important to control imaging of installed thermal media  20 . Such control need may depend on, inter alia, design and/or operation of a dual-sided thermal printer  10 , and/or design and/or construction of installed media  20 . In particular, where one or more print heads  50  and  60  and/or print elements  54  and  64  are situated substantially across from one another in a printer  10 , such as shown in the embodiments of  FIG. 2E  and  FIG. 2F , control of heat output by a first print head  50  and/or element  54  opposite a second print head  60  and/or element  64  may be required or desired when dual-sided imaging is to occur in proximate regions of a first and a second side of installed media  20 . Such control may be required or desired to image particular media and/or to provide uniform printing of the media  20 , as described in U.S. application Ser. No. 11/314,613 and filed on Dec. 21, 2005, which application is hereby incorporated by reference herein for all purposes. 
   In some embodiments, heat output for printing by a first thermal print head  50  may be reduced in a region of thermal media  20  where heat is or will be output by a second thermal print head  60 . Likewise, heat output for printing by a second thermal print head  60  may be reduced in a region of thermal media  20  where heat is or will be output by a first thermal print head  50 . In other embodiments, heat output by a first and/or a second thermal print head  50  and  60  may be increased in a region of thermal media  20  where heat is or will be output by a respective second and/or first thermal print head  60  and  50 . 
   Control of an amount of heat output by a first and/or a second thermal print head  50  and  60  for printing may be effectuated by controlling a voltage and/or a current applied to the first and/or second thermal print head  50  and  60 , including a duration thereof. Alternately or additionally, control of heat output by a first and/or a second thermal print head  50  and  60  may be effectuated by controlling a number of print elements  54  and/or  64  used to image a particular portion of print media. For example, where two or more print elements  54  and  64  associated with a respective first and second thermal print head  50  and  60  are provided proximate to a region of thermal media  20  desired to be imaged, a number of print elements  54  and/or  64  used to image respective regions of the first and/or second media side may be varied. 
   In one embodiment, a first number of print elements  54  associated with a first print head  50  may be used to image a region of a first side of thermal media  20  proximate to a region where printing is and/or will be provided on a second side of the media  20  by a second thermal print head  60 , while a second number of print elements  54 , greater than the first number, may be used to image a region of the first side of the media  20  when a proximate region of the second side of the thermal media  20  is not and/or will not be imaged by the second thermal print head  60 . In other embodiments, for example where it is desired to image only one side of thermal media  20  in a particular region, a first number of print elements  54  associated with a first print head  50  may be used, while where it is desired to image both the first and a second side of thermal media  20  in the particular region a second number of print elements may be used. 
   Regardless of the means, variations in a basis for control of heat output for printing by a two-sided imaging direct thermal printer  10  are possible, including controlling heat output by a first and/or a second thermal print head  50  and  60 , and/or one or more associated print elements  54  and  64 , based on (i) a spacing of the print heads  50  and  60  and/or print elements  54  and  64 , (ii) an amount of media  20  along a media feed path  25  between print heads  50  and  60  and/or print elements  54  and  64 , (iii) a speed of printing, (iv) media construction and/or type, (v) combinations of the same, and the like. Further, regardless of the means or basis, control over heat output for printing by a two-sided imaging direct thermal printer  10  may be provided for through operation of a dual-sided printing function switch  70 , a controller or processor  90  associated with the dual-sided printer  10 , an external control signal from an associated host computer such as a POS system, an ATM, a self-service kiosk, a personal computer, and the like. 
     FIG. 3A  shows a two-sided thermal document in the form of a receipt  110  having transaction detail  120  such as issuer identification, time, date, line item entries and a transaction total printed on a first (front) side of the receipt  110 .  FIG. 3B  shows custom information  130  printed on a second (back) side of the receipt  110  contemporaneous with the transaction detail information  120  printed on the front. For example, the custom information  130  could include further or duplicate transaction information, a coupon (as shown), rebate or contest information, serialized cartoons, conditions of sale, document images, advertisements, security features, ticket information, legal information such as disclaimers, warranties and the like, or other information. Further, the custom information  130  may be targeted based on recipient/purchaser identity, transaction data, transaction detail  120 , store inventory or specials, manufacturer inventory or specials, and the like, or randomly selected from a database of possible options, among other means. 
     FIG. 3C  shows a two-sided receipt  150  with a portion of the associated transaction detail printed on the front side  160  of the receipt  150 .  FIG. 3D  shows the reverse side  170  of the receipt  150  shown in  FIG. 3C , where the remaining portion of the associated transaction data is shown printed on the reverse side  170  of the receipt  150 . Indicia such as “Front Side,” “Reverse Side,” “Side  1 ,” “Side  2 ,” or the like may be included on the two sides  160  and  170  of the receipt  150  (as shown) to denote the two-sided nature of the receipt  150  or the respective side  160  and  170  of the receipt  150  being viewed. Identifying indicia such as a receipt or transaction number, terminal number, store identifier, date, time or the like may also be printed on both sides  160  and  170  of the receipt  150  to enable ready identification of the receipt  150  from either side  160  and  170  and/or of copied images of the two sides  160  and  170 . 
     FIG. 4  shows a perspective view of an exemplary dual-sided direct thermal receipt printer  200  for point-of-sale (POS) terminal application. 
     FIG. 5  schematically shows a partial centerline elevation view of the dual-sided direct thermal receipt printer  200  of  FIG. 4 , in a closed (operating) position. As shown, the printer  200  includes a print head  210 , a platen  220  and a guide roller  230  all coupled to a supporting arm or base structure  240 . The print head  210 , platen  220  and guide roller  230  are on one side of the feed path  250  of the dual-sided thermal print media taken off a supply roll  260 . The printer  200  also includes a print head  270 , a platen  280  and a guide roller  290  all coupled to a pivotable supporting arm or cover  300 , which pivots about a hinge line  310  to allow, for example, paper replacement and servicing. When the arm  300  is in the closed position (as shown), the media paper may be engaged between the print head  210  and opposed platen  280 , between the print head  270  and the opposed platen  220 , and between the guide rollers  230  and  290 . Contact pressures with, and tension of, the print media are maintained by, for example, spring loading of the various printer elements using springs  320 ,  330  and  340 . 
   As further shown in  FIG. 5 , a printer  200  may further include a spring  350  for the pivotable supporting arm or cover  300  to enable opening of the cover  300  at a controlled rate, and thereby avoid, for example, uncontrolled closing of the cover  300  through force exerted on the cover  300  via the acceleration of gravity. A sensor  360 , may further be provided to detects a paper out condition, and produce a signal which can be used to disable printing, notify a POS operator (not shown) to replace the supply roll  260 , and the like. A sensor  360  may also be provided to identify regions of the media for printing, including identifying regions comprising sense marks or other preprinted material. 
   A printer  200  may also include an electronically activated mechanical cutting or knife blade mechanism  370  to sever the print media upon completion of a print task such as printing of a transaction receipt. A serrated edge  380  may also be included to enable manual severing of the print media at the end of a transaction, when a media print roll is replaced or reloaded, and the like. 
   As illustrated in  FIG. 5 , a printer  200  may also comprise control electronics for controlling operation of the printer  200 . The control electronics may include a motherboard  390 , a microprocessor or CPU  90 , and memory  80 , including one or more DRAM and/or NVRAM print buffer memory elements. The printer  200  further may comprise a communications controller  396  for communicating with one or more host or auxiliary systems such as a POS terminal (not shown) for input of data to, and output of data from, the printer  200 . Communication controller  396  may support USB, Ethernet and/or wireless communications (e.g., 802.11, 802.15, and IR), among others. Data for printing would typically be supplied by a host POS terminal (not shown) communicating with the printer  200  via the communication controller  396 . Supplemental data for printing, such as product and or discount coupon information can also be supplied by, for example, a network server (not shown) providing data directly to the printer  200  using the communication controller  396 , or indirectly through the host POS terminal. The supplemental data for printing may vary depending upon the goods or services sold, an in-store, chain-wide or manufacturer special, identification of the customer, and/or one or more other transaction aspects. 
   The memory  80  of the dual-sided direct thermal printer  200  may have a predefined print data storage area to store one or more blocks of predefined print data to be repetitively printed on one or both sides of the print media. The blocks of predefined print data may comprise, for example, a store identifier, a logo, a coupon, an advertisement, and the like. The predefined print data may be printed along with data submitted by application software associated with the POS terminal (not shown) on the same or an opposite media side. Where multiple data blocks are stored in the predefined print data storage area, the blocks may be alternatively selected for printing through use of the hardware or software switch  70 , as may be the location on or side of the media they are printed, and the like. 
   A dual-sided direct thermal printer  200  as described may be operated with legacy or other application program software developed for use with, for example, a single-sided direct thermal printer. In such case, the dual-sided logical or mechanical printing function switch  70  may be used to enable dual-sided thermal media printing using input from the single-sided application program software. 
   The switch  70  may enable activation and deactivation of one or more dual-sided printing functions in response to a manual setting, or to a command message or escape sequence transmitted to the printer  200  via the communication controller  396 , or a configuration setting though a driver or utility interface as previously described. In one example, the single-sided application software conventionally controls printing of submitted data on one media side, while the switch  70  enables printing of, for example, additional information on the opposite media side. This functioning would allow realization of dual-sided direct thermal printer benefits with legacy software, before or without having to invest in custom printing mode applications or other new application program or interface software. 
   A one-sided printing application program may thus control direct thermal printing on one side of a media sheet, where the dual-sided printing function switch  70  is configured to enable thermal printing on the other media side. The data printed under control of the function switch  70  may be a block of data stored in the memory  80  of the printer  200  for repetitive printing as previously described. The block of data to be printed may, for example, be selected by a command or an escape message, as a function of data received from the one-sided printing application program such as transaction detail data, or it may be randomly selected, as previously described. 
   By enabling printing on one side of a media sheet by a one-sided printing application program, and enabling printing on the opposite side of the sheet by operation of the function switch  70  activating and deactivating one or more dual-sided direct thermal printing functions, requirements for application program software may thus be simplified. Legacy or other application program software for one-sided printing which do not directly operate all dual-sided direct thermal printing functions may thus be used to print on one side of a media sheet. Stored, or other data received by, or available to the printer  200  may then be printed on the opposite side of the sheet media. 
   In another example, the dual-sided direct thermal printer  200  may be operated to print data provided by legacy or other application program software on both sides of a media sheet. In such case, the dual-sided logical or mechanical printing function switch  70  is used to enable a further mode of operation of the dual-sided thermal printer  200  to divide and apportion data received from the single-sided application program software among the two media sides. Such a split can be even, e.g., half of the data is printed on each side of the media, or can be otherwise apportioned to maximize use of the media in light of any preprinted material on or supplemental information to be printed with the single-sided application program provided data, and the like. 
   As a further option, the dual-sided thermal printer  200  may be designed to accommodate the ability to print on the front and back, or either side independently, of a thermal media. 
     FIG. 6  schematically shows an example partial drive or gear plane elevation view of the dual-sided direct thermal receipt printer  200  of  FIGS. 4 and 5 , with the cover  300  in a closed position. As shown, the platens  220  and  280  are coupled at their ends for rotation by a first gear  400  and a second gear  410 , respectively. The first gear  400  is in operative contact with the second gear  410 , as well as a third gear  415 . The third gear  415  is coupled to a motor  416  for driving the first and second gears  400  and  410 , and their respective platens  220  and  280 . As shown, when rotated in a clockwise direction by the motor  416 , the third gear  415  drives the first and second gears,  400  and  410 , and their respective platens,  220  and  280 , such that the print media is directed over the respective print heads away from the print roll  260  in a forward feed direction. Likewise, when rotated in a counterclockwise direction by the motor  416 , the third gear  415  drives the first and second gears,  400  and  410 , and their respective platens,  220  and  280 , such that the print media is directed over the print heads toward to the print roll  260  in a backward feed or retract direction. Alternate motor and gear relations, as well as drive means (e.g., belt drives, direct drives, friction drives and the like), and rotations are, however, possible. 
   The printer  200  of  FIG. 6  also includes one or more additional sensors, such as one or more limit switches  420 , which provide signals for use in controlling operation, or signaling condition of the printer  200 . For example, a signal from a first limit switch  420  can be used to notify a POS operator that the cover  300  of the printer  200  is not properly closed. Likewise, a signal from the first limit switch  420  can be used to allow automatic deactivation of printing until the cover  300  is in a properly closed position. Similarly, a signal from a second limit switch  420  can be used in combination with a signal from the first limit switch  420  to ensure the cover  300  is properly closed. This may include a determination that the cover  300  is properly aligned with respect to the base  240  such that opposing print heads ( 210  and  270 ) and platens ( 280  and  220 ) are in full and uniform contact across their width in advance of printing, and the like. 
   Additionally, a signal from a further sensor (not shown) may be used to indicate that a proper pressure for printing is obtained between opposing print heads and platens. Likewise, a further sensor (not shown) may be used to indicate a proper tension is obtained on the print media, or a locking mechanism such as one or more latch  430  is properly engaged. As for the limit switch  420 , a signal from any such sensor may used to trigger notification of an improper condition to an operator (not shown), such as through the sending of an error message to a POS terminal (not shown), and/or through disabling some or all printer operations until the condition is corrected, and the like. 
   A locking mechanism, such as one or more latch or detent  430 , is also provided with the printer  200  to secure the pivotable supporting arm  300  in place, and maintain the proper positioning of opposing print heads ( 210  and  270 ), platens ( 220  and  280 ) and guide rollers ( 230  and  290 ), including maintaining a proper contact pressure across the width of the media, and/or tension of the media along the media feed path  250  during printer operation. As shown, the latch  430  is biased by a spring  432  against a stop  434 , and is released by pressing of a button  435 . In addition to moving the latch  430  away from the stop  434 , depression of the button  435  applies sufficient upward force on the cover  300  to separate the print heads from the platens in light of the applied contact pressure and frictional forces, and thereby allow the cover  300  to be freely opened. 
   The latch  430 , in combination with the spring  350 , also prevents the pivotable supporting arm  300  from striking the supporting arm or base structure  240 , or other components of the printer  200  such as the print head  210 , platen  220  and/or guide roller  230  if the pivotable supporting arm or cover  300  is opened and dropped. 
     FIG. 7  schematically shows a partial centerline elevation view of the dual-sided direct thermal receipt printer  200  of  FIG. 4  with the pivotable supporting arm or cover  300  in an open position to allow, for example, insertion and replacement of two-sided printing media rolls  260 , and other servicing. A link  435  connects to (as shown) or is otherwise in operative contact with the cover  300  and base structure  240  to limit the open position of cover  300 . The link  435  may further comprise a damping element to damp motion of the cover  300  such as where the cover  300  is opened under force of the spring  350 . The combination of the link  435  and spring  350  comprise a mechanism for controlling the motion of the pivotable supporting arm or cover  300  for the two-sided direct thermal printer  200  to mitigate the potential for damage to printer components upon opening and closing of the cover  300 . More generally, a mechanism for controlling the motion of the pivotable supporting arm or cover  300  may include one or more torsional elements such as springs, and/or one or more frictional or damping elements such as shock-absorbers or bushings to control the motion of the pivotable support arm or cover  300  such as by slowing down its rate of opening. 
     FIG. 8  schematically shows a partial centerline elevation view of a variation of the dual-sided direct thermal receipt printer of  FIG. 4 , with the cover  300  in a closed position. As shown the illustrated printer  440  includes two print heads  450  and  460 , and two platens  470  and  480  on opposite sides of a print media feed path  250 . Print heads  450  and  460  are substantially in-line and face substantially opposed directions. As a result, the feed path  250  of the print media is substantially a straight line path given the substantially in-line orientation of the print heads  450  and  460 . This configuration facilitates frontal exiting of the print media from a machine associated with the printer  440  such as an ATM, kiosk or other self-service terminal. The in-line feed path also facilitates automation of media replacement including allowing the media to be automatically drawn from the first print head  450  and platen  470  to and through the second print head  460  and platen  480 . This contrasts with the printer  200  shown in  FIG. 5  where the print heads  210  and  270  are angled to face substantially normal directions, and the media feed path  250  takes an upward turn for the print media to exit the top of the printer  200 . Automatic media feed and retraction may, however, also be provided for with the print head and platen configuration of  FIG. 5 , among other configurations (e.g.,  FIGS. 2A through 2F ). Further, additional print head ( 452  and  462 ) and platen and/or feed roller ( 472  and  482 ) orientations, and resultant media feed paths ( 250 ), such that illustrated in  FIGS. 13 and 14 , are also possible. 
     FIG. 9  schematically shows a partial drive or gear plane elevation view of the dual-sided direct thermal receipt printer  440  of  FIG. 8 . In  FIG. 9  first and second gears  490  and  500  are respectively coupled to first and second platens  470  and  480 . This configuration allows the first platen  470  and second platen  480  to be independently driven by one or more motors (not shown) operatively coupled to the first  490  and second  500  gears, respectively. In such case, the first platen  470  can be independently driven so as to pull the print media away from the roll  260  and direct it toward the second platen  500 . Similarly, the second platen  480  can be independently driven so as to pull the print media away from the roll  260  and/or first platen  490 , and direct it out of the printer  440 . Likewise, the first and/or second platens can be independently driven so as to pull the print media away from the exit back into the printer  440 , and/or away from the second print head  460  and platen  480 . Such a dual drive media feed mechanism may be used to facilitate automatic retraction of the print media such that printing may occur on a portion of the media that would otherwise be unused owing to the offset in the spacing along the paper path of the print heads  450  and  460 . Likewise, such a dual drive feed mechanism may be used to delay printing on one side of a print media as compared to the other side such as by allowing printing to occur on all or a portion of one side of the print media followed by a retract of the media for printing on all or a portion of the other side of the print media. Separate, forward and/or backward drive (not shown) of the media such as the media roll  260  may also be provided. 
     FIG. 10  schematically shows a partial centerline elevation view of a further variation of the dual-sided thermal printer  440  of  FIG. 8 . In this instance, the printer  440  is designed to support print media such as a sheet roll  260  outside of the cover  300  to facilitate ready replacement of print media and/or relatively large media roll  260  sizes. As for the printer  440  shown in  FIG. 8 , the print heads  450  and  460  in the dual-sided thermal printer illustrated in  FIG. 10  are substantially in-line and face substantially opposed directions. As a result, the feed path  250  of the print media is also substantially in-line facilitating automated replacement and loading of print media. One or more media guides  505  are further provided to align the media, and thereby facilitate automated media loading and feed. 
     FIG. 11  schematically shows a partial drive or gear plane elevation view of the dual-sided direct thermal receipt printer  440  of  FIG. 10  wherein first and second drive gears  470  and  480  are attached to respective first and second platens  490  and  500  for independently and/or collectively moving print media in a forward and/or backward direction along a media feed path  250 . 
     FIG. 12  schematically shows a partial centerline elevation view of a further variation of the dual-sided direct thermal receipt printer of  FIG. 4 . This printer configuration utilizes a modular construction in which the printer  510  has a first and a second print head  520  and  530  which are part of plug-in modules  540  and  550 , respectively. Likewise, the printer  510  has first and second platens  560  and  570  which are part of plug-in modules  580  and  590 , respectively. Such modular construction facilitates manufacture of a printer with a single print head and platen for operation in a single-sided print mode while simultaneously providing for ready, future upgrading to two-sided printer functionality in the field. Likewise, the modular construction allows readily replacement and/or upgrade of the various modules  540 ,  550 ,  580  and  590  for increased future functionality, or as the various print heads  520  and  530 , and platens  560  and  570  wear out. 
   In alternate configurations, a modular printer  510  may have a first print head  520  and first platen  560  coupled into a single, first module, and a second print head  530  and second platen  570  coupled into a single, second module. Similarly, in a further variation, a first print head  520  and second platen  570  may be coupled into a first module, and the second print head  530  and first platen  560  may be coupled into a second module. Additional module print head and/or platen configurations and couplings are possible. 
   Regardless of the configuration, any of the attachments  600  used to attach any of the various modules to the cover  300  and/or base  240  may comprise static or dynamic (e.g., spring mounted) couplings for reducing mechanical stress on the various modules, and assisting in maintaining a desired contact pressure on the print media by the respective print heads and platens during print operations. In practice, each of the cover  300  and base  240  are appropriately modified (not shown) to readily accept the respective modules and associated attachments  600 . It should be noted that the attachments  600  may comprise electrical contacts, electro-mechanical contacts, and/or mechanical contacts depending on the attachment module type (e.g., platen, print head, and platen and print head), and the like. 
   It will now be appreciated that a dual-sided thermal printer has been described for printing on both sides of thermal print media. Some alternative and/or additional embodiments will now be described. 
   Fixed Upper Support Arm or Cover 
   While the above described dual-sided direct thermal printer examples illustrate an upper support arm or cover  300  as being pivotable with respect to a lower support arm or base  240  about a hinge pin  310 , the upper support arm or cover  300  may also be fixably attached, or otherwise coupled to the lower support arm or base  240 , and not pivotable. In one example, the upper support arm or cover  300  is attached to the lower support arm or base  240  using one or more fasteners such as screws. 
   Dual-Sided Thermal Printer Print Head Configuration 
   In equipment with automated or automatic replacement media feed (e.g., automated in-feed of replacement thermal paper rolls or fan-fold stacks), such as ATM&#39;s and various other self-service terminals, a dual-sided thermal printer such as printer  440  of  FIG. 10  typically has print heads  450  and  460  that are substantially in-line or in-plane. In retail applications with manual replacement roll paper feed, a dual-sided thermal printer such as printer  200  of  FIG. 5  can have print heads  210  and  270  angled with respect to one another, e.g., at an angle of about 90 degrees to, for example, permit top exit of a receipt. Such angled orientation permits a reduced spacing between the print heads  210  and  270  for minimization of the length of unprinted areas or white spaces on opposite sides of the media in a once-through direct thermal printing process. Appropriate angles, aspect and location of one print head with respect to another and/or their respective platens will vary based on the printer end use and needs of the specific print media and/or print environments (i.e. kiosk printer, pharmacy printer, POS printer, and the like). 
   Optimized Print Head Spacing 
   The lateral spacing of a first and a second thermal print head (e.g., spacing  55  of  FIG. 1A ) may be optimized to allow heat applied to a first side of a two-sided imaging element by the first print head to sufficiently dissipate so that heat applied to a second side of the imaging element by the second print head does not cause unwanted printing on the first side. The optimum spacing is a function of the amount of heat applied by the respective print heads, the imaging material and/or dyes utilized in the imaging element, properties of any coatings utilized in the imaging element including coating thickness and thermal conductivity, properties of any substrate utilized in the imaging element including substrate thickness and thermal conductivity, speed of printing, and the like. 
   Dual-Sided Thermal Printer Guide Roller Configuration 
   A dual-sided thermal printer  200  or  400  may comprise a pair of guide rollers  230  and  290  for maintaining a proper tension of print media, and guiding the media through the printer. The rollers can be respectively coupled to pivoting opposing arms that support print heads and platens. For example a print head, a platen and a guide roller can be coupled to a supporting arm or base structure on one side of the media feed path. Opposing print head, platen and guide roller elements can be coupled to a second supporting arm, e.g., a structure that pivots with respect to the base structure, that aligns on the opposite side of the media feed path. Each print head may thus be opposed by a platen and the guide rollers may oppose or be in proximate relation to one another across the media feed path. Contact pressure may be maintained against the print media by one or more springs urging the print heads against the platens. Similarly, one or both guide rollers may be spring loaded to maintain appropriate roller contact pressure with the print media. In an alternative configuration, two print heads may directly oppose one another across the feed path without platens. In one such configuration, each of two supporting arms may be coupled to an associated guide roller and one of the print heads. In another configuration a guide roller can comprise a pair of spaced coaxially aligned guide rollers. The space between the coaxially aligned guide rollers allows the addition of a variable size paper guide to accommodate different width media; whether rolls, fan-fold, sheet or otherwise. 
   Platen Configuration 
   In a dual-sided direct thermal printer such as the printer  200  shown in  FIG. 5 , platens  220  and  280  may have a substantially round cross-section. Likewise, in alternate embodiments, the platens  220  and  280  may have a substantially square or rectangular cross section, or otherwise present a substantially flat surface to either or both of the print heads  210  and  270 . Further, regardless of the profile, each of the platens  220  and  280  may be substantially the same size and/or have substantially the same cross-sectional profile and/or area, or one platen may differ in one or more respects with regard to the other, including length. 
   Depending on their design and/or use, one or more platens or platen surfaces may comprise one or more coatings or materials. For example, where a platen is used to feed the media through the printer, as for platens  220  and  280  of  FIG. 5 , the platen and/or its surface may comprise a material providing for enhanced friction such as natural and/or artificial rubber, variations are possible. Likewise, where the platen comprises a flat, sheet-type surface, the platen may comprise or be coated with a material providing for decreased friction such as polytetrafluoroethylene (PTFE), and/or electroless nickel incorporating PTFE (e.g., PTFE particles dispersed in an electroless nickel matrix), although variations are possible. 
   In one embodiment, the platens have a substantially round cross-section of approximately ⅜ to ½ inch diameter, and are substantially the same length. 
   In another embodiment, two thermal print heads are substantially opposite each other across a media feed path and act as respective platens for each other. In such case, one or both of the thermal print heads may comprise or be coated with a friction reducing material. 
   Drive Mechanism 
   In a dual-sided direct thermal printer, media feed may be provide for by one or more belts, wheels, rollers, and the like. In one example, shown in  FIG. 6 , drive rollers in the form of platens  220  and  280  on opposite sides of a media feed path  250  are coupled for rotation by gears. Alternately, either of both platens can be jointly coupled or independently driven by, inter alia, (1) one or more belts or bands, (2) two or more meshing gears, (3) one or more direct drives, and/or (4) one or more direct contact frictional elements, any or all of which may be in operative contact with, or directly driven by, one or more drive motors or actuators. 
   Likewise, upstream and downstream platen drive mechanisms, such as motor driven upstream and downstream platens, which are capable of individual or simultaneous operation, may be provided. Advantageously, where it is desired to move an imaging element in a forward direction, power is provided to drive the downstream platen, while where it is desired to move the imaging medium in a reverse direction, power is provided to drive the upstream platen. The dual drive feed mechanism allows automatic retraction of an imaging element such that printing may occur on a portion of the element that would otherwise be un-used owing to an off-set in the spacing  55  of print heads in a two-sided printer, and the like. The automatic retraction feature could also be implemented by a single motor driving both platens, e.g., where the platens are commonly coupled for rotation by one or more belts, or two or more gears as shown in  FIGS. 6 and 9 , and the like. 
   Uniform Print Head Contact Pressure 
   A desired uniform print head to platen contact pressure across the width of a two-sided imaging element can be provided during printer operation. The mechanism for this may include one or more springs on or associated with the print heads, platens and/or common supports therefore, e.g., springs  320 ,  330  and/or  350  shown in  FIG. 5 , spring loaded attachments  600  shown in  FIG. 12 , and the like. 
   Printer Operating Permissives 
   Control electronics, such as one or more sensors  100 ,  360  and  420  in the form of one or more paper sensors to detect media presence and/or printing thereon, and contact switches to detect proper mechanical arrangement and alignment of print elements for printing, and the like, can be used to permit (e.g., as permissives) and control operation of a dual sided thermal printer and/or dual sided thermal printer functionality. For example, one or more contact sensors may be provided to allow printer operation only when the first and second print heads are properly positioned with regard to the first and second platens, a proper contact pressure is achieved between the first and second print heads and their respective platens, and/or a supporting pivotable arm structure or cover  300  is properly secured, etc. Likewise, one or more optical sensors may be provided to detect presence of and printing on print media for enabling and controlling location of thermal printing on the media. 
   Retractable Print Mechanism 
   A mechanism (not shown) may be provided for individually retracting one or both print heads and/or platens in a two-sided printer to allow the printer to function in a single-sided print mode while minimizing wear on the unused print head or platen. The retracting mechanism may be manually or automatically, e.g., electronically or electromechanically, actuated. 
   Printer Functionality 
   A two-sided thermal printer and associated firmware for two-sided printing may advantageously support the following functions: 
   1. Single-sided print mode. This print mode supports basic single-sided printing, allowing operation of thermal print heads on one side of a media feed path. 
   2. Double-sided with single-side command mode (e.g., buffered print mode). This print mode will allow for the storage of some or all of the print data by the printer in advance of imaging the media. Print data received from, for example, a POS terminal (not shown) is stored in a print buffer  80  until an end-of-transaction message such as a knife (cut) command is received. Once the knife command is received the firmware will then divide the buffered print data and designate a first portion, such as a first half of the data, for printing on the first (e.g., front) side of the media, and a second portion of the data, such as the remaining half, for printing on the second (e.g., back) side of the media. After the designated data is printed on the respective first and second sides, then a physical knife cut by the knife blade mechanism  370  of roll media, a line feed to an end of sheet media, and the like, may be performed completing the print job. The double-sided buffered print mode may be enabled by manually setting of one or more DIP or other switches or jumpers, through use of a diagnostic set up routine, by sending an escape code or command, e.g., the 1F 11 xx command, to the printer, and the like. 
   3. Double-sided with double-side command mode (e.g., application controlled print mode). This print mode allows for control of double-sided print functionality by an application program such as transaction software running on a POS terminal. Such application may control printing through controlling the location of print data on a first (e.g., front) and a second (e.g., back) side of media such as a receipt, when and in what sequence the application data is to be printed, and the like. The double-side command mode may store application print data in one or more buffer or other memory locations prior to printing. Likewise it may select predefined data from one or more buffer or other memory locations to print at one or more locations of one or both sides of the media with or without application print data. The double-sided command mode may be initiated through receipt of one or more double-sided print commands, a diagnostic routine, through manual setting of switches or jumpers, and the like. 
   4. Double-sided print mode with predefined data. When operated in this mode, predefined data from one or more of predefined print data storage facilities (e.g., buffer or other memory locations) may be printed on one side of a two-sided thermal media, and application data, such as POS terminal transaction information, may be printed on another side separate from the predefined data print side. When this mode is selected, the printer may initiate printing on both sides of the media, or store the application print data in the data storage facility  80  until a command for initiating double-sided printing is received. The double-sided print mode with predefined data may be initiated through receipt of one or more associated commands, through use of a diagnostic routine, through manual setting of switches or jumpers, and the like. 
   Printer Capabilities 
   A dual-sided thermal printer  200  preferably has the following capabilities: 
   Print Speed: 4.0 inches per second (IPS) when 55 watt power is provided. This includes front and back printing. 
   Print Speed: 6.7 IPS when 75 watt power is provided. This includes front and back printing. 
   Print Buffer: Up to 450 print lines at 7.5 lines per inch (LPI) assuming 44 characters/line Logo/Text Storage. 
   Preferred Default Limitations 
   When printing, it is preferred that the character attributes be the same for the front and the back side of the receipt. For example if double high printing is printed on the front side then the printing on the back side would also be double high. Alternate front/back characters sizes and/or fonts are, however, possible. 
   When printing in the double-sided buffered print mode and the capacity of the print buffer  80  is exceeded, the printer can distribute the buffered data for printing on each side of the media, and then print the remaining data on one side, e.g., the front side of a receipt, prior to performing a knife cut. Alternately, the printer can distribute and print the buffered among the two sides then refill the print buffer  80  with additional print data, and continue this process until an end-of-transaction message such as a knife cut command, is received. 
   Status Update Messages 
   The following table defines exemplary dual-sided thermal printer sensor or state information specified by each identifier, and meanings of the lower 4 bits of the 3rd byte for identifier values: 
   
     
       
         
             
             
             
             
           
             
                 
             
             
               Identifier 
               Description of sensor or state RTC Sensor Bit if 
                 
                 
             
             
               Value 
               Applicable for 7167/7197 (Note: RTC might be 
               State 
             
             
               (Hex) 
               different for other printers 
               Value 
               Meaning 
             
             
                 
             
           
          
             
               12 
               Slip Motor Jam 
               1 
               Motor in Jam state 
             
             
                 
               RTC Response (10 04 03) - Bit 2 
               0 
               Normal State 
             
             
               13 
               Knife Condition 
               1 
               Knife in Error Condition 
             
             
                 
               RTC Response (10 04 03) - Bit 3 
               0 
               Normal State 
             
             
               14 
               Unrecoverable Error 
               1 
               Unrecoverable Error 
             
             
                 
               RTC Response (10 04 03) - Bit 5 
                 
               Encountered 
             
             
                 
                 
               0 
               Printer has been Reset 
             
             
               15 
               Thermal Print Head Temperature 
               1 
               Out of operating range 
             
             
                 
               RTC Response (10 04 03) - Bit 6 
               0 
               Normal operating range 
             
             
               16 
               Power Supply Voltage 
               1 
               Out of operating range 
             
             
                 
               RTC Response (10 04 03) - Bit 6 
               0 
               Normal operating range 
             
             
               17 
               Printer Paper Sensor 
               1 
               Paper Present 
             
             
                 
               RTC Response (10 19 01) - Bit 0 
               0 
               No Paper 
             
             
               18 
               Printer Reset 
               1 
               Printer Physical Reset Took 
             
             
                 
               RTC Response (10 19 01) - Bit 6 
                 
               Place 
             
             
               19 
               Presenter Mechanism State 
               1 
               Presenter in Error 
             
             
                 
               RTC Response (10 19 02) - Bit 0 
               0 
               Presenter in Normal State 
             
             
               1A 
               Paper jam status 
               1 
               Printer is in Jam State 
             
             
                 
               RTC Response (10 19 02) - Bit 1 
               0 
               Printer in Normal State 
             
             
               1B 
               Kiosk Door State 
               1 
               Door Open 
             
             
                 
               RTC Response (10 19 02) - Bit 3 
               0 
               Door Closed 
             
             
               1C 
               Black Mark Detection Status 
               1 
               Detection Failure 
             
             
                 
               RTC Response (10 19 02) - Bit 5 
               0 
               Normal Status 
             
             
               1D 
               Print Head Condition 
               1 
               Print Head Damaged 
             
             
                 
               RTC Response (10 19 02) - Bit 6 
               0 
               Print Head OK 
             
             
               1E 
               Flip Mechanism Door State 
               1 
               Door Open 
             
             
                 
               No RTC equivalent 
               0 
               Door Closed 
             
             
               1D 
               Double-side buffer exceed 
               1 
               Received data exceed double- 
             
             
                 
               No RTC Equivalent 
                 
               side buffer 
             
             
                 
                 
               0 
               Double-side buffer adequate 
             
             
                 
             
          
         
       
     
   
   Exemplary Printer Setting Change Commands: 
   
     
       
         
             
             
             
             
           
             
                 
             
             
               m 
                 
               n 
                 
             
             
               (Hex) 
               Function 
               (Hex) 
               Function 
             
             
                 
             
           
          
             
               60 
               Thermal Printing Mode 
               00 
               Single-Sided Mode 
             
             
                 
                 
               01 
               Double-Sided Mode with Single-Side 
             
             
                 
                 
                 
               command 
             
             
                 
                 
               02 
               Double-Sided Mode with Double-Side 
             
             
                 
                 
                 
               Command 
             
             
                 
                 
               03 
               Double-Sided Mode with Predefined 
             
             
                 
                 
                 
               Data 
             
             
               61 
               Upside Down Printing for Double- 
               00 
               Front: Normal, Back: Normal Front: 
             
             
                 
               Side 
               01 
               Upside down, Back Normal Front: 
             
             
                 
                 
               02 
               Normal, Back: Upside Down Front: 
             
             
                 
                 
                 
               Upside Down, Back Upside Down 
             
             
                 
                 
               03 
             
             
               62 
               Swap Front Side and Back Side 
               00 
               Not Swap Front side and Back sides 
             
             
                 
                 
               01 
             
             
               63 
               Predefined Bottom/Top Message 
               00 
               No Message Bottom Message on Front 
             
             
                 
                 
               01 
               Top Message on Back Both Bottom 
             
             
                 
                 
               02 
               Message on Front and Top Message 
             
             
                 
                 
               03 
               on Back 
             
             
               64 
               Minimum Receipt Length 
               00 
               No Minimum Receipt Length in inches 
             
             
                 
                 
               01-FF 
               for Minimum receipt length 
             
             
               65 
               Reprint when Error Occurs 
               00 
               Resume printing from last error line 
             
             
                 
                 
               01 
               Reprint the error page 
             
             
                 
             
          
         
       
     
   
   Exemplary Two Side Printer Commands (e.g., Real Time Commands): 
   Exemplary Select Thermal Printing Mode Command: 
   ASCII: US ′ n 
   Hexadecimal: 1F 60 n 
   Decimal: 31 96 n 
   Value of n: 
   0=Single-Sided Mode 
   1=Double-Sided Mode with Single-Side Command 
   2=Double-Sided Mode with Double-Side Command 
   3=Double-Sided Mode with Predefined Data 
   Default: n=0 (Single-Sided Mode). Selects the thermal printing mode; single-side or double-side print mode. If single-side mode is selected, thermal printing can only be executed on one (e.g., front) side of receipt paper. If double-side mode is selected, printing can be executed on front side or/and backside of receipt paper. With selection n=0, printing format is same as existing firmware. 
   Selection n=1 (Double-Sided Mode with Single-Side Command), print data is buffered and split in two parts. The first part of the print buffer will be printed on a first (e.g., front) side and the second part of the print buffer will be printed on a second (e.g., back) side of the media such as receipt paper. The printing of the data may be executed by, for example, sending a knife or other end of transaction command to the printer (Exception: The command Select Thermal Printing Side and Start Double-Sided Printing would be ignored). 
   Selection n=2 (Double-Side Mode with Double-Side Command), print data is selectively buffered and printed on the front and back side of media such as receipt paper upon command from an application program, such as software executed by a POS terminal. In addition to print data received from an application program, such as POS terminal transaction information, such print data may include predefined print data stored in one or more buffer or other memory locations of the printer. 
   Selection n=3 (Double-Side Mode with Predefined data), application program data, such as POS terminal transaction data, may be buffered and/or printed on a first side of thermal media, and predefined data, such as one or more of an advertisement, incentive, coupon, rebate or other information, may be printed on a second side of the thermal media. Data printed on a given media side may be switched such that, for example, transaction data is printed on a front side and predefined data is printed on a back side, and vice versa. Likewise, a given predefined data block may be printed only once for a given document such as a receipt. Document length is determined by the print data (e.g., transaction versus predefined) requiring the greater amount space. 
   The setting of this command is not stored into NVRAM/Flash memory. 
   The Printer Setting Change command (e.g., 1FH 11H) is used to store the setting. 
   Sending a 1Fh 62h will print data 
   Exemplary Select Thermal Printing Side Command: 
   ASCII: US a n 
   Hexadecimal: 1F 61 n 
   Decimal: 31 97 n 
   Value of n: 
   0=Front Side 
   1=Back Side 
   Default: 0 (Front Side) 
   Selects the thermal printing side: front side or back side. This command executes when the Thermal Printing Modes, Double-Side Mode with Double-Side Command is selected (n=2), otherwise, this command is ignored. This command is valid for subsequent lines. 
   If data exceeds buffer size, printer prints out automatically and print buffer is cleared. Printer mode remains unchanged. 
   Exemplary Limitations: 
   Character attributes are same for both sides. For example, when the front side printing characteristic is Double wide, the back side printing characteristic is also Double wide. When either side of printing area is lager than printing buffer (TBD: XX inch), printer will start printing automatically then printer return to single-sided printing. 
   Exemplary Start Double-Sided Printing Command: 
   ASCII: US b 
   Hexadecimal: 1F 62 
   Decimal: 31 98 
   Starts double-sided printing. This command executes if the Thermal Printing Modes, Double-Side Mode with Double-Side Command is selected (n=2), otherwise, this command is ignored. The paper length is determined by the longest side of the print data. 
   Exemplary Select or Cancel Upside Down Printing for Double-Side Mode Command: 
   ASCII: US c n2 
   Hexadecimal: 1F 63 n 
   Decimal: 31 99 n 
   Value of n: 
   Bit 0=0: Cancel Front Side upside down printing 
   Bit 0=1: Enable Front Side upside down printing 
   Bit 1=0: Cancel Back Side upside down printing 
   Bit 1=1: Enable Back Side upside down printing 
   Printing side (Front/Back side) is physical side of printing. 
   Default: 0 (Cancel upside printing for both sides) 
   This command makes the first line becomes the last line, and the first character of first line becomes the last character of last line. This command is valid in Double-Side Mode. Before starting double-side printing, only the last received select or cancel upside down printing command is effective. The setting of this command is not stored into NVRAM/Flash memory. The Printer Setting Change command (e.g., 1FH 11H) is used to store setting. 
   Exemplary Swap Front Side and Back Side Command: 
   ASCII: US d n 
   Hexadecimal: 1F 64 n 
   Decimal: 31 100 n 
   Value of n: 
   0: Cancel swap. 
   1: Swap Front Side and Back Side. Original Front Side data is printed on backside and original Back Side data is printed on front side. 
   Default: 0 (Cancel swap) 
   This command will swap the printing of the front side data and backside data when the printer is in Double-Side Mode. Before swapping Front Side and Back Side, the Front Side data is printed via Front Side thermal head. After swapping, the Front Side data is printed via Backside thermal head. 
   Before starting double-side printing, only the last received swap front side and backside command is effective. 
   The setting of this command is not stored into NVRAM/Flash memory. 
   The Printer Setting Change command (e.g., 1FH 11H) is used to store setting. 
   Exemplary Limitations: For Double-Side Mode w/Single-Side Command, if Logo is printed immediately before paper cut, after swap, the printing pattern on Front Side (Backside before swap) will have blank (e.g., 35 mm long) area. 
   Download Predefined 1-line Text Message into Printer Buffer ROM 
   ASCII: US e n k d1 d2 . . . dk NUL 
   Hexadecimal: 1F 65 n k d1 d2 . . . dk 0 
   Decimal: 31 101 n k d1 d2 . . . dk 0 
   Value of n: 
   n: The line number. n=0, 1, 2, 3. 
   k: The character attribute 
   d1, d2, . . . , dk: Strings of 1-line Text Message. Strings terminated with NUL 
   This command will download one line of text into ROM. The message is used in all Double-Side Modes. User can select to automatically add a 1-line/2-line text message at bottom of Front Side or/and at top of Back Side. Front Side uses line 0 and line 1 and Back Side uses line 2 and line 3. Printing side (Front/Back side) is logical side of printing. 
   Exemplary Settings of Download Command Character Attribute: 
   
     
       
         
             
           
             
                 
             
             
               K 
             
             
                 
             
           
          
             
                 
             
          
         
         
             
             
             
             
          
             
                 
               Bit 7 
               0: Italic Mode off 
               1: Italic Mode on 
             
             
                 
               Bit 6 
               0: Inverse video mode 
               1: Inverse video 
             
             
                 
                 
               off 
               mode on 
             
             
                 
               Bit 5 
               0: Underline mode off 
               1: 1 dot underline 
             
             
                 
               Bit 4 
               0: Emphasize mode 
               1: Emphasize mode 
             
             
                 
                 
               off 
               on 
             
             
                 
               Bit 3 
               0: Double width off 
               1: Double width on 
             
             
                 
               Bit 2 
               0: Double height off 
               1: Double height on 
             
             
                 
               Bit 1 
               00H: ANK/ = 
             
             
                 
               &amp; 0 
               01H: Double Byte 
             
             
                 
                 
               Asian character 
             
             
                 
                 
               10H: Single Byte 
             
             
                 
                 
               Asian Character 
             
             
                 
                 
             
          
         
       
     
   
   Exemplary Enable predefined bottom/top message Command: 
   ASCII: US f n 
   Hexadecimal: 1F 66 n 
   Decimal: 31 102 n 
   Value of n: 
   Bit 0=0: Disable predefined bottom message on front side 
   Bit 0=1: Enable predefined bottom message on front side 
   Bit 1=0: Disable predefined top message on back side 
   Bit 1=1: Enable predefined top message on back side 
   Default: 0 (Disable predefined bottom and top message) 
   When this function is enabled, printer will automatically add a 1-line or 2-line text message at the bottom/top of front side/backside of receipt. This command is only valid in Double-Side Mode (All w/Single-Side Command and w/Double-Side Command and w/Predefined data). The setting of this command is not stored into NVRAM/Flash memory. 
   The Printer Setting Change command (e.g., 1FH 11H) is used to store setting. 
   Exemplary Select nth Macro Command: 
   ASCII: US g n 
   Hexadecimal: 1F 67 n 
   Decimal: 31 103 n 
   Value of n: 1 to 25 
   Default: n=1 
   Select nth macro for definition or execution. 
   If this command is received during definition of a macro, the current definition will be cleared. The same commands are used to define macro and execute macro as below. 
   Start or End Macro Definition (GS :) 
   Execute Macro (GS ^) The Macro size is 2048 bytes each. 
   Exemplary Limitations: Characters exceeded one line will be ignored. If command sequence is US e n k NUL, printer will clear the nth line message in Flash ROM. If only one line is defined, printer will only print the defined line. Some attributes may not be supported—Script mode, 2-dot underline mode, Double strike mode, 90° Left/Right Rotation, Black/Red, Print Start Position, Character size≧3. Attribute cannot be changed in one line. 
   Exemplary Start or End Predefined Back Side Printing Command: 
   ASCII: US h 
   Hexadecimal: 1F 68 
   Decimal: 31 104 
   Starts or ends Predefined Back Side Printing and stored into the printer buffer ROM. Predefined back side printing definition begins when this command is received during normal operation and ends when this command is received during Predefined back side printing definition. If the printer receives a second “Start or End Predefined Back Side Printing” immediately after previously receiving a “Start or End Predefined Back Side Printing” the printer will clear Predefined Back Side Printing. If this command is received during a Macro&#39;s definition (GS :), the current Macro definition will be cleared. During definition of predefined backside printing, receive command GS: (Start or End Macro Definition) will make the current definition be cleared. 
   Exemplary Define Minimum Receipt Length Command: 
   ASCII: US i n1 n2 
   Hexadecimal: 1F 69 n1n2 
   Decimal: 31 105 n1 n2 
   Range of n1: 0-255 
   Range of n2: 0-255 
   Default: 
   n1=0 
   n2=0 
   This command defines the minimum media (e.g., receipt) length to start the conversion from single-side to double-side printing. This setting is enabled for only “Double-Sided Mode with Single-Side Command”. 
   Exemplary Print Media Check Mode Command: 
   Value n: 
   0=Media Checking Disabled Mode 
   1=Media Checking Enabled Mode 
   The Print Media Check Mode can be enabled or disabled in printer diagnostics. The setting (value) is saved into EEPROM. When Media Checking Enabled Mode is selected, the Select Thermal Printing Mode Command (e.g., 1F 60 n) may be ignored depending on the combination of identified media (e.g., single-sided, double-sided, non-thermal, and the like) and the Select Thermal Printing Mode Command setting (e.g., Single-Sided Mode, Double-Sided Mode with Single-Side Command, Double-Sided Mode with Double-Side Command, and Double-Sided Mode with Predefined Data). 
   In one embodiment the Print Media Check Mode Command is set to Media Checking Enabled, and the Exemplary Select Thermal Printing Mode Command is set to Double-Sided Mode with Single-Side Command. Upon execution of the check, if the media is determined to be double-sided thermal, operation will continue in the selected Double-Sided Mode with Single-Side Command. However, if the media is determined to be single-sided thermal, operation will proceed pursuant to the Single-Sided Mode, thereby ignoring (e.g., overriding) the Select Thermal Printing Mode Command (e.g., 1F 60 n) setting. 
   Further detail of one embodiment is provided in the following table. 
   
     
       
         
             
          
             
                 
             
             
               Paper Match Status Print Mode Table 
             
          
         
         
             
             
             
             
             
             
          
             
               Selected 
                 
                 
                 
                 
               1F 60 n 
             
             
               Thermal Print 
               Detected 
               Paper Matching 
               Operating 
               Error Message 
               Command 
             
             
               Mode 
               Media 
               Status (1) 
               Print Mode 
               Print (2) 
               Status 
             
             
                 
             
             
               Single-Sided 
               Single- 
               01 
               Single-Sided 
               No print 
               Ignore 
             
             
               Mode 
               Side 
                 
               Mode 
             
             
                 
               Double- 
               01 
               Single-Sided 
               No print 
               Valid 
             
             
                 
               Side 
                 
               Mode 
             
             
               Double- 
               Single- 
               10 
               Single-Sided 
               Print 
               Ignore 
             
             
               Sided Mode 
               Side 
                 
               Mode 
             
             
               with Single- 
               Double- 
               01 
               Double-Sided 
               No print 
               Valid 
             
             
               Side 
               Side 
                 
               Mode with 
             
             
               Command 
                 
                 
               Single-Side 
             
             
                 
                 
                 
               Command 
             
             
               Double- 
               Single- 
               10 
               Double-Sided 
               Print 
               Valid 
             
             
               Sided Mode 
               Side 
                 
               Mode with 
             
             
               with Double- 
                 
                 
               Double-Side 
             
             
               Side 
                 
                 
               Command 
             
             
               Command 
               Double- 
               01 
               Double-Sided 
               No print 
               Valid 
             
             
                 
               Side 
                 
               Mode with 
             
             
                 
                 
                 
               Double-Side 
             
             
                 
                 
                 
               Command 
             
             
               Double- 
               Single- 
               10 
               Double-Sided 
               Print 
               Valid 
             
             
               Sided Mode 
               Side 
                 
               Mode with 
             
             
               with 
                 
                 
               Predefined 
             
             
               Predefined 
                 
                 
               Data 
             
             
               Data 
               Double- 
               01 
               Double-Sided 
               No print 
               Valid 
             
             
                 
               Side 
                 
               Mode with 
             
             
                 
                 
                 
               Predefined 
             
             
                 
                 
                 
               Data 
             
             
                 
             
             
               (1) e.g., Bit 4 &amp; 5 of 1F 6C and 1F 6D Commands 
             
             
               (2) e.g., “WARNING: Non 2ST Paper Loaded” 
             
          
         
       
     
   
   As indicated in the above described embodiment, if single-sided rather than two-sided thermal media is detected, an error message may be printed on the thermal side of the single-sided media indicating to a user that two-sided thermal paper is not loaded. Other methods of user notification, including one or more visible, audible, and/or tactile alarms, are also possible. 
   Exemplary Return Thermal Printing Mode Batch Command: 
   ASCII: US I n 
   Hexadecimal: 1F 6C n 
   Decimal: 31 108 n 
   Values of n: 
   1=Thermal printing mode status 
   When n=1 the Return Thermal Printing Mode Batch Command transmits the status after all data currently in the receive buffer has been processed. 
   Exemplary Return Thermal Printing Mode Real Time Command: 
   2.14.15.1 ION USB or RS232 
   ASCII: US m n 
   Hexadecimal: 1F 6D n 
   Decimal: 31 109 n 
   2.14.15.2 Standard USB 
   ASCII: Since this command is used by Control transfer, the command strings are not defined. 
   Hexadecimal: 06 00 n (bRequest=0x06, wValue=0x00 n) 
   Decimal: 06 00 n 
   Value of n: 
   1=Thermal printing mode status 
   When n=1 the Return Thermal Printing Mode Real Time Command transmits the current printer mode status. 
   For both the Return Thermal Printing Mode Batch Command and the Return Thermal Printing Mode Real Time Command, the returned thermal printing mode status has the following bit designations: 
   
     
       
         
             
          
             
                 
             
             
               Thermal Printing Mode Status Bit Designation Table 
             
          
         
         
             
             
             
             
             
          
             
               Bit 
               Off/On 
               Hex 
               Decimal 
               Function 
             
             
                 
             
          
         
         
             
             
             
             
             
          
             
               1, 0 
               — 
               00 
               0 
               Single-Sided Mode Selected 
             
             
                 
               — 
               01 
               1 
               Double-Sided Mode with Single-Side 
             
             
                 
                 
                 
                 
               Command Selected 
             
             
                 
               — 
               10 
               2 
               Double-Sided Mode with Double-Side 
             
             
                 
                 
                 
                 
               Command Selected 
             
             
                 
               — 
               11 
               3 
               Double-Sided Mode with Predefined 
             
             
                 
                 
                 
                 
               Data Selected 
             
             
               2 
               — 
               0 
               0 
               Not defined. Fixed at 0. 
             
             
               3 
               Off 
               0 
               0 
               Front Side selected (valid only 
             
             
                 
                 
                 
                 
               in Double-Sided Mode with 
             
             
                 
                 
                 
                 
               Double-Side Command) 
             
             
                 
               On 
               1 
               8 
               Back Side selected (valid only 
             
             
                 
                 
                 
                 
               in Double-Sided Mode with 
             
             
                 
                 
                 
                 
               Double-Side Command) 
             
             
               4, 5 
               — 
               00 
               0 
               Media detection not finished. 
             
             
                 
               — 
               01 
               16 
               Detected media and selected print mode 
             
             
                 
                 
                 
                 
               match. 
             
             
                 
               — 
               10 
               32 
               Detected media and selected print 
             
             
                 
                 
                 
                 
               mode differ. Operating print mode set 
             
             
                 
                 
                 
                 
               pursuant to the Paper Match 
             
             
                 
                 
                 
                 
               Status Print Mode Table. 
             
             
                 
               — 
               11 
               48 
               Not defined. 
             
             
               6 
               — 
               0 
               0 
               Not defined. Fixed at 0. 
             
             
               7 
               — 
               0 
               0 
               Not defined. Fixed at 0. 
             
             
                 
             
          
         
       
     
   
   As described above, depending on the selected print mode and detected media type, bits 4 and 5 of the Return Thermal Printing Mode Batch Command and the Return Thermal Printing Mode Real Time Command will have the following designations: 
   
     
       
         
             
          
             
                 
             
             
               Thermal Print Mode Status Bit 4 and 5 Designations 
             
          
         
         
             
             
             
          
             
               Selected Thermal Print Mode 
               Detected Media 
               Bit 4 &amp; 5 Status 
             
             
                 
             
             
               Single-Sided Mode 
               Single-Side 
               01 
             
             
                 
               Double-Side 
               01 
             
             
               Double-Sided Mode with Single- 
               Single-Side 
               10 
             
             
               Side Command 
               Double-Side 
               01 
             
             
               Double-Sided Mode with 
               Single-Side 
               10 
             
             
               Double-Side Command 
               Double-Side 
               01 
             
             
               Double-Sided Mode with 
               Single-Side 
               10 
             
             
               Predefined Data 
               Double-Side 
               01 
             
             
                 
             
          
         
       
     
   
   Formulas: 
   To set minimum document/receipt length to two inches at the default horizontal motion unit of 1/203 inches, send the four-byte string: 
   US i 150 1 
   Where 2 inches=406/203, and 406=(1×256)+150. 
   Exemplary Limitations: 
   Character attributes are same for both sides. For example, when the front side printing characteristic is Double wide, the back side printing characteristic is also Double wide. When either side of printing area is larger than printing buffer, printer will start printing automatically then printer return to single-sided printing. 
   Exemplary Configuration Menu Double-Sided Printing Settings: 
   Press the Paper Feed Button for the double-side printing settings you want. 
   Defaults are marked with an asterisk (*). 
   ** SET Thermal Printing Mode? 
   YES&gt;Long Click 
   NO&gt;Short Click 
   Single-Side*&gt;1 Click 
   Double-Side w/Single Cmd&gt;2 Clicks 
   Double-Side w/Double Cmd&gt;3 Clicks 
   Double-Side w/Predefined Data&gt;4 Clicks 
   Enter code, then hold Button Down at least 1 second to validate 
   ** SET Upside Down Mode? 
   YES&gt;Long Click 
   NO&gt;Short Click 
   F:Normal, B:Normal*&gt;1 Click 
   F:Up Down, B:Normal&gt;2 Clicks 
   F:Normal, B:Up Down&gt;3 Clicks 
   F:Up Down, B:Up Down&gt;4 Clicks 
   Enter code, then hold Button DOWN at least 1 second to validate 
   ** SET Swap Front &amp; Back? 
   YES&gt;Long Click 
   NO&gt;Short 
   Click 
   Disable*&gt;1 Click 
   Enable&gt;2 Clicks 
   Enter code, then hold Button DOWN at least 1 second to validate 
   ** SET Bottom and Top Message? 
   YES&gt;Long Click 
   NO&gt;Short Click 
   Top: Disable, Bottom: Disable*&gt;1 Click 
   Top: Enable, Bottom: Disable&gt;2 Clicks 
   Top: Disable, Bottom: Enable&gt;3 Clicks 
   Top: Enable, Bottom: Enable&gt;4 Clicks 
   Enter code, then hold Button DOWN at least 1 second to validate 
   ** SET Minimum Receipt Length? 
   YES&gt;Long Click 
   NO&gt;Short Click 
   Disable*&gt;1 Click 
   5 inch&gt;2 Clicks 
   10 inch&gt;3 Clicks 
   15 inch&gt;4 Clicks 
   Enter code, then hold Button DOWN at least 1 second to validate 
   ** SET Reprint when Error Occurs? 
   YES&gt;Long Click 
   NO&gt;Short Click 
   Resume Print from Error Line*&gt;1 Click 
   Reprint the Error Page&gt;2 Clicks 
   Enter code, then hold Button DOWN at least 1 second to validate 
   The above description is illustrative, and not restrictive. In particular, design, layout and/or designation of a first and/or a second print head, platen, gear, and the like, as well as a front and a back media side or a top or a bottom media portion, may vary among embodiments. 
   Further, many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the embodiments should therefore be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. 
   The Abstract is provided to comply with 37 C.F.R. § 1.72(b) and will allow the reader to quickly ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 
   In the foregoing description of the embodiments, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. Likewise, various features are described only with respect to a single embodiment for purposes of avoid repetition. This method of disclosure is not to be interpreted as reflecting that the claimed embodiments have more or less features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in more or less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the description of the embodiments, with each claim standing on its own as a separate exemplary embodiment.