fig9 is an abstract drawing representing a closed - case removable expansion card 100 , i . e ., an expansion card that may be inserted into and removed out of a closed - case computer host . the card is especially suitable for use in a portable host , such as a pda . in accordance with the present invention , the expansion card of fig9 includes a connector 141 for i / o interconnect and a slot 121 for a removable memory . fig9 shows the i / o interconnect 140 and removable memory 120 disengaged from the removable expansion card . fig1 is an abstract drawing representing the construction detail of the upper 105 and lower 110 frame members of the removable expansion card 100 of fig9 . an opening 111 is provided in the lower frame 110 for receiving the connector 141 for i / o interconnect . fig1 is an abstract drawing representing an exploded view of the removable expansion card 100 of fig9 including the outer frame , inner pcb 115 , and connectors . visible for the first time in the view of fig1 , a second opening 113 is provided in the lower frame 110 for receiving the connector 150 for host interconnect . additionally , a slot 112 is provided on both sides of the opening 111 to aid in the alignment and retention of the connector 141 , and a slot 114 is provided on both sides of opening 113 to aid in the alignment and retention of the connector 150 . an opening 116 is provided in the pcb for receiving the connector 141 . fig1 a is an abstract drawing representing a view of the removable expansion card 100 of fig9 with the outer frame members removed , and a removable memory 120 roughly aligned with the contact fingers 180 to which it mates within the removable expansion card . circuitry 160 is provided , including i / o adapter circuitry , removable memory adapter circuitry , and application - specific circuitry . a support shelf 170 supports , aligns , separates , and isolates the underside of the contact fingers 180 from the circuitry 160 . fig1 b is an abstract drawing representing a cut away side view of the removable expansion card 100 of fig9 with the removable memory 120 inserted into the removable expansion card . fig1 a is an abstract drawing representing an end view silhouette of the removable expansion card 100 of fig9 . fig1 b is an abstract drawing representing a cross - sectional view silhouette of the upper frame member 105 of the removable expansion card 100 of fig9 . guides 190 provide alignment and support for removable memory inserted via slot 121 . in a preferred embodiment , the expansion card 100 and associated host connector 150 are compatible with the type ii compactflash card as described in the previously referenced compactflash specification . the i / o connector 141 is compatible with a pc - card industry standard honda - style 15 - pin connector . the slot 121 , removable memory 120 , and removable memory adapter circuitry of circuitry 160 , are compatible with the multimediacard as described in the previously referenced multimediacard system summary . in a first embodiment of the invention , circuitry 160 includes i / o adapter circuitry and removable memory adapter circuitry . the i / o adapter functionality may include one or more of , but is not limited to , ethernet , serial port , audio , telephone , antenna , and special - function interfaces such as bar code and other scanners . the removable memory adapter functionality may include one or more of , but is not limited to , main memory expansion , mass - media emulation , and other host - based special - purpose memory applications . in accordance with a second embodiment , circuitry 160 further includes application - specific circuitry for which the management of the removable memory is an ancillary function to the primary function of the specific application . specific examples of such application - specific expansion cards having both i / o and removable memory are provided in later sections . in preferred implementations of both of the first and second embodiments mentioned above , the functions performed by the removable memory are those of a multimediacard adapter as illustrated in the multimediacard adapter section of the multimediacard system architecture diagram of fig4 . if the removable memory is being used to provide host - base memory expansion , such as described for the first embodiment , then the host must provide the functionality illustrated by the application and application adapter sections of fig4 . if the removable memory is being used at least sometimes as an ancillary memory ( at least sometimes private ) to the application - specific circuitry contained on the expansion card , such as for the second embodiment , then the application - specific circuitry must provide the application and application adapter section functionality , or else the application - specific circuitry must call on host services for such functionality . examples of known techniques for making and using other types of memory adapter circuitry for closed - case expansion cards or with flash memory are found in the previously referenced &# 39 ; 145 , &# 39 ; 426 , &# 39 ; 584 , &# 39 ; 774 , and &# 39 ; 108 patents , among others . examples of known techniques for making and using i / o adapter and application - specific circuitry for functions implemented in closed - case expansion cards and with flash memory are found in the previously referenced &# 39 ; 374 , &# 39 ; 577 , &# 39 ; 774 , and &# 39 ; 108 patents , among others . the top and bottom frames may be composed of metal or plastic . in a preferred embodiment , the top and bottom frame portions each have a plastic base augmented with an outer metal plate over much of the interior region of the large panel surface of each portion . the metal plate extends to the edges of the panel at the connector ends of each portion and is attached to both connectors . in addition , smaller metal strips , or ears , on both sides at the finger - grip end ( opposite to the host connector ) extend from the plate to the edges of the panel and continue onto the sides . the frame kit is assembled and the side strips are sonically welded together on both sides of the casings . the welded strips and plates form a single continuous metal band around the top and bottom frames that permanently physically retains the assembled kit . i / o devices may be interconnected with the expansion card via three different embodiments . first , a pc - card industry - standard honda - style 15 - pin connector may be used with a mating detachable cable . detachable cables are preferred for light - duty applications where a continuous i / o device connection is neither needed nor desired . second , a fully integrated fixed cable , having a molded strain relief may be used . such a fixed cable maintains solid contact in high vibration environments , is protected against lateral stress , and seals out dust . fixed cables are preferred for dedicated industrial or field applications . third , at least a portion of the i / o device may be abutted and attached ( often via a snap - in - place mechanism ) directly to the expansion card , obviating the need for either a detachable or fixed cable . cableless snap - on i / o devices are preferred for small mostly self - contained i / o devices that permit a compact pda , expansion - card , i / o - device combination that handles physically as a single piece of equipment . in the instant invention , such snap - on i / o devices must make allowance for the removable memory . fig7 illustrates a pda 200 equipped with a removable expansion card 100 having both i / o interconnect 140 and removable memory 120 in accordance with the present invention . the application specific circuitry of the expansion card may be used in conjunction with application specific software running on the pda . this permits the application specific circuitry of the expansion card to make use of the output ( e . g ., display , sound ) and input ( e . g ., tablet , buttons , any i / o ports ) capabilities of the pda for user interface functions associated with the specific application . in particular the pda &# 39 ; s display / input - tablet provides for virtual controls and visual indicators for the application . fig8 illustrates some of the various types of i / o for which the pda and removable expansion card of fig7 may be equipped . application - specific functions may include special - function mixed - signal electronics , special - function i / o , special - function data - pumps , and special - function accelerators . the present invention enables general - purpose portable hosts to perform application - specific functions requiring dedicated rom . a first large rom - based application category is that of prerecorded media , such as music , audio , video , and text ( for books , newspapers , and other publications ). a second large rom - based application category is customization for programmable devices , such as games , language translators , and other devices having “ personality ” modules . the present invention also enables general - purpose portable hosts to perform application - specific functions requiring non - volatile read / write memory for data - capture , data - logging , data - checkpoints or backups , transaction logging , and data - transport . in the illustrated embodiments the non - volatile read / write memory is flash memory in accordance with the standard multimediacard . such removable flash - memory - based application - specific functions have particular utility to medical and other data acquisition , secure commerce , financial and personal productivity devices making use of unique removable memories for each of multiple individuals , projects , or accounts . the removable flash - based memory is also well suited where “ sneaker - net ” is a viable data transport . provided manual / user intervention is acceptable , and depending on the speed of data link i / o incorporated into the expansion card , the physical transport of a removable memory device between a pda - based expansion card and an external system may provide the best solution to fast local transport of large data - sets . for similar reasons , the use of removable memory devices may provide the best solution to rapidly reconfiguring an application - specific expansion card to initiate a large program or use a large data sets . the use of labeled , color - coded , or otherwise distinctive , removable memory devices also may provide the best solution for ease of use for users needing to select a particular program or data set from many for reconfiguring an application specific expansion card . the present invention permits a general purpose pda to be customized ( specially adapted ) for use as a portable / wearable media player , at the highest - level of functionality not unlike a portable compact disk player . such a player uses the removable memory to store and playback digitally encoded media such as music , audio , or video . in a preferred embodiment the player makes use of the mpeg layer 3 standard for digital audio encoding , generally known as mp3 . another embodiment makes use of the microsoft digital audio standard . other aspects of a preferred embodiment include an integral am / fm receiver , a connector for a headset with an integral antenna for the receiver , and an auto - start on insert feature that initiates the media playback upon insertion of the removable memory . the pda &# 39 ; s display / input - tablet provides the virtual controls and visual indicators for the media player . in accordance with the present invention , an expansion card having i / o and removable memory is inserted into a computer host . the i / o is coupled to a receiver capable of receiving a large number of broadcast messages and services . the removable memory contains subscriber services information for each individual user . the expansion card uses the subscriber services information to filter out messages and services not applicable to the present status of the subscriber . the pda &# 39 ; s display / input - tablet provides the virtual controls and visual indicators for the display and access of captured messages and services . in accordance with the present invention , an expansion card having i / o and removable memory is inserted into a computer host , a bar - coding peripheral is connected to the i / o portion of the card , and a removable memory card is inserted into the memory slot of the card . after each scan the scanned information is transferred through the i / o connection to the host computer for processing . additionally , a backup copy of the scanned information is stored on the removable memory . should the computer host fail or should the operator need to verify scans , the backup can be interrogated with the same or a different host . the present invention permits a general purpose pda to be customized as a portable / wearable personal environmental monitor . equipped with the appropriate sensors and application - specific circuitry for sensor signal processing , such a device performs time - stamped data logging of environmental attributes such as ionizing radiation , temperature , and humidity . similarly , a portable / wearable personal medial monitor data logs health - related attributes such as pulse , temperature , respiration , and blood pressure . the pda &# 39 ; s display / input - tablet provides the virtual controls and visual indicators for the monitoring devices . the combined i / o interconnect and removable memory of the present invention also permits a general purpose pda to be customized ( specially adapted ) for use as a data logging diagnostic monitor or time - based control device . it is known that the diagnostic connectors of certain vehicles can be adapted to interface with pdas for real - time monitoring of critical vehicle subsystems . the present invention permits such diagnostic monitoring data to be communicated via the i / o interconnect and logged to the removable memory . such a tool facilitates tracking subsystem performance over extended periods of time , and permits real - time and deferred graphics of time - varying system performance attributes . the pda &# 39 ; s display / input - tablet provides the virtual controls and visual indicators for the diagnostic monitor . although the present invention has been described using particular illustrative embodiments , it will be understood that many variations in construction , arrangement and use are possible within the scope of the invention . for example the number of i / o interconnects , removable memories , contact fingers , number and type of application - specific circuits , and the size , speed , and type of technology used may generally be varied in each component of the invention . the invention is not limited to the standard compactflash form factor , but other closed - case removable expansion card form factors are equally applicable . nor is the invention limited to use of the standard multimediacard , as other types of removable memory or media may also be employed . functionally equivalent techniques known to those skilled in the art may be employed instead of those illustrated to implement various components . the present invention is thus to be construed as including all possible modification and variations encompassed within the scope of the appended claims .