High-density removable expansion module having I/O and second-level-removable expansion memory

摘要

The utility of portable computer hosts, such as PDAs (or hand-helds), 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.