Abstract: Computer hosts, such as PDAs, are customized for use in bar code scanner applications through use of a first-level removable expansion module having bar code related circuitry and a slot and internal connector for a second-level removable memory. In combination with a connected or attached I/O device for scanning bar codes, these modules provide embedded bar code scanning I/O adapter and/or application-specific functions as well as second-level removable memory functions. The removable memory may be used to store a backup copy of the scanned data for restoration in the event the original scan data is lost or corrupted. Restoration may occur using any interface compatible with the removable memory. The removable memory may also be used by the bar code scanner application specific circuitry within the first-level removable expansion module.

Abstract: The utility of portable computer hosts, such as PDAs (or handhelds), is enhanced by methods and apparatus for removable expansion cards having application specific circuitry, a second-level-removable memory, and optional I/O, in a number of illustrative embodiments. In addition to providing greater expansion utility in a compact and low profile industrial design, the present invention permits memory configuration versatility for application specific expansion cards, permitting easy user field selection and upgrades of the memory used in conjunction with the expansion card. Finally, from a system perspective, the present invention enables increased parallelism and functionality previously not available to portable computer devices.