Ed Perratore
As committee members work on a new PCMCIA specification that will add bus mastering, a 32-bit data path, and 3.3-V operation, users continue to grapple with incompatibilities in current products. PCMCIA devices are getting closer to full interoperability across different PCs. But users of PCMCIA fax modems, LAN adapters, and other devices are finding that the reality of 100 percent compatibility approaches the goal only asymptotically--coming ever closer but never arriving.
Today's PCMCIA scene features a mixture of PCMCIA devices that may work perfectly well with one brand of PC but not with another. "Let's face it, the [PCMCIA] spec was originally designed as a memory-card manager," says Ray Bridenbaugh, marketing manager for American Megatrends (Norcross, GA), a company tha
t develops system motherboards, BIOSes, and peripheral cards. "PCMCIA is not like PCI [Peripheral Component Interconnect]. The PCI spec needed little revision. But PCMCIA has now become a broad application bus, and this evolution of use has resulted in a challenge in maintaining compatibility across all applications."
Other incompatibilities can occur with devices that implement features not specified in the specification, such as the so-called Type IV, 16-mm cards. Toshiba's T4600 and T4700 notebooks have a 16-mm slot that accepts the company's dual-RJ-11-port modem. But the modem won't fit in standard Type I, II, and III slots.
Dan Sternglass, president of Databook (Ithaca, NY) and head of the PCMCIA committee's compatibility task force, offers a simple rule for solving compatibility problems: Call your PC vendor to see if the PCMCIA device you want to buy will work with your PC, and use the latest driv-ers. "If people do that, they find that most everything out there works."
A more per
manent solution revolves around the PCMCIA committee's efforts to tackle compatibility issues, which include developing a minimum required function set for the CIS (Card Information Structure). The host chip and card services use the CIS to properly set up IRQs (interrupt requests), I/O memory base, and other settings. Eventually, the committee hopes to make PCMCIA cards compatible across hardware platforms.
Compatibility will become more important as PCMCIA's popularity increases as a peripheral standard. "All of a sudden, this neat technology has a solid marketing purpose that will help drive it into legitimacy," says Bridenbaugh. "The stepchild has been adopted."
Illustration: Chart: PCMCIA Card Sales Forecast
This chart shows worldwide sales projections for both memory and I/O devices over the next five years; 1993 figures are based on actual sales.
The Memory-Card Manager Grows Up
