People Can’t Memorise Computer Industry Acronyms – how very true: striking a blow against the ugly collections of letters, the association that mnemonic represents, the Personal Computer Memory Card International Association, has, with the third release of its mobile computing technology, rechristened it the PC Card standard. Unfortunately for plain English, the Association lost heart there, and retained its full name. PC Card technology appeared five years ago as memory cards for mobile computers. Since then the technology has progressed in fits and starts, dogged by compatibility issues, but the Association quotes studies that say that by 1997 more than 88% of all portable computers will have a PC Card slot. The technology is intended to enable mobile computer users to insert and remove the cards easily to add memory, modem capabilities and network access, but this swappability has not always been possible. With the latest release the PCMCIA has attempted to address issues of compatibility, v ery necessary if the technology is to progress and appear as a standard in all notebook computers.

Mandatory

The PCMCIA is confident that the standard’s expanded Card Information Structure, guidelines for developers, and media storage formats have successfully addressed these issues. But only the Card Information Structure is mandatory if a maker wants to claim the device as a PC Card. The Association says that the standard has been developed with an eye to the future, so that cards will be ready for things like 100Mbps Ethernet. It has also joined forces with the Japan Electronic Industry Development Association, JEIDA, believing this will give the standard a global feel and, in fact, the PC Card standard is an amalgamation of the two organisations’ specifications. PC Card’s original use as add-in Flash memory was attractive, because it was robust, had low power requirements and offered high performance. But at the outset it had little or no software support. In 1991 the standard’s second release introduced specifications for input-output, making possible input-output devices such as modems. The next release introduced software support in the form of Card Services and Socket Services. Card Services software enables the allocation of system resources once Socket Services detects that a PC Card has been added to the system. The Socket Services provide a BIOS- level software interface that isolates other software from the underlying hardware and identifies how many sockets the systems has, and when a PC Card has been inserted or removed while the system is running. By release 2.0 there were some software enablers facilitating communication with the host, but these were all hardware-specific.

By Maya Anaokar

The references Type I, II and III define thicknesses, 3.3mm, 5mm and 10.5mm, with Type I being used for memory, II for input-output devices, and III for devices that require bulkier components. Although the technology has proliferated, many personal computer manufacturers have found it unattractive because of the need for layers of software and hardware, all from different manufacturers, further exacerbating problems of compatibility. The fact that the PCMCIA has never insisted that its members’ products undergo testing, and has no intention of doing so, and that paid-up membership enables makers to stamp the PCMCIA logo on their products, has added to the confusion, and disappointment surrounding the technology. Despite the introduction of the new standard, the Association does not plan to present the standard for International Standards Organisation ratification. All it is planning is what it calls a series of Card Fests, the first one scheduled for next month in San Francisco, where it will encourage adoption of the new standard. The two most important enhancements in the PC Card standard is the Card Information Structure, the software on the card that enables the card to be self-configuring and enables more comprehensive dialogue between the PC Card and the host. The other major change

is the introduction of the specifcation for the 32-bit CardBus interface; the Association says that it’ll take some time to implement, given the changes in both the hardware and software needed, but that once up and running, the bus master interface will transmit data at rates of up to 132Mbps at 33MHz, raising performance closer to Peripheral Component Interconnect buses and making the technology suitable for multimedia, video and Asynchronous Transfer Mode applications. CardBus is likely to remain the domain of high-end notebooks; 16-bit cards will be able to operate in CardBus compatible hardware, but not vice versa. The PC Card standard also includes specifications for 3.3V cards and power management. A hardware direct memory access capability has been added that will mean developers do not have to emulate this function in software; in practical terms it should expand potential applications of the cards. But these new specifications call for new machines. The PCMCIA is at pains to point out that it has attempted to make all new cards as backwards-compatible as possible, and says it is not attempting to obsolete the millions of cards out there already, but some new PC Cards will not work on existing machines.

Multifunctional cards

The drop in voltage is an example of where new cards will not work unless dual voltage capabilities are built in. Another concern has been how users will distinguish between 16-bit and 32-bit cards; the PCMCIA says this will be down to labelling but the pin-out will be just the same. The PCMCIA reckons computer makers will be coming out with computers with new slots in a matter of months, ahead of the first PC Card standard-compliant cards. The new standard supports multifunction cards and the PCMCIA is keen to encourage their proliferation; the Association says that the hardware in this case is not an issue, rather it’s the software for the card itself. It’s keen because multifunctional cards serve to reduce the need to remove and replace cards, making a limited number of slots go further and eliminating what it calls ‘slot crunch.’ The PCMCIA also hopes that the resolution of compatibility issues will encourage PC Cards move into other areas such as television set-top boxes, desktop machines, cards for font storage for printers and various consumer uses. In addition to the new standard, a great deal of hope rests with the much-delayed Windows95, which is to have Plug & Play capabilities that will eliminate, so people say, the last of the compatibillity problems that have affected PC Card technology. Carl Stork, drector of the Windows hardware programme at Microsoft Corp said at CeBIT that he expected Windows95 to become the standard for implementation of PC Cards and that vendors will write device drivers for Windows 95, obviating the need for any card and socket services.