PCMCIA cards teeter on the edge of interoperability
“The PCMCIA card socket will become the portable computing bus of the future,”
declared market analysis firm Dataquest, Inc. (San Jose, CA) in 1991–and it
was right. Over the last year the outpouring of products based on the standard
has risen from a trickle to a flood as manufacturers scramble to meet the
demands of an increasingly computer-savvy and nomadic end user. Even those who
aren't “computer dweebs” want PCMCIA with its promise of plug-and-play
interoperability and widely promoted goof-proof features. These features, while
long-awaited, have not been forthcoming–until now that is.
Originally introduced as release 1.0 in May 1990, the PCMCIA migrated from a
memory-card standard to incorporate I/O in release 2.0 later that year. Around
the same time, the lowest level of a layered software architecture, called
Socket Services, was introduced. Since then, a second layer–Card Services (or
Client Driver)–has been added to allow the host computer to drive the card.
Once compiled for a given operating system, these services ensure the socket is
ready for a card and that the card will operate on any PCMCIA-ready system,
regardless of the manufacturer.
Until recently, the Card Services software was card-specific and had to be
installed on the host. Now, a third software layer, called Super Client, comes
installed on the computer and handles cards generically. It allows the system
to talk to any manufacturer's I/O device, be it a fax/modem, SCSI adapter, or
disk drive. The manufacturer looking for an opportunity to differentiate itself
from the pack may use the fourth and latest software layer, which handles the
graphical user interface. This interface can be implemented pretty much however
the vendor wishes.
These improvements and additions to the PCMCIA specification, along with others
condensed into Release 2.1, may be the enabling factors for what has long been
heralded as a new era in computer plug-and-play operation. According to Carl
Perkins, president of New Media Corp. (Irvine, CA), that era may well have
arrived, thanks to the company's SystemSoft Card and Socket Services. Assuming
the industry follows his company's lead and concentrates on the software end of
the specification, Perkins believes that plug-and-play is but a heartbeat away.
The foundation for SystemSoft rests on five criteria New Media believes to be
critical:
1. The PCMCIA card is not required to be present when the computer is booted.
2. The card can be removed and inserted at any time–even while being accessed
by the host.
3. Client software must be card-aware and fully cognizant of the presence or
absence of the card.
4. Cards must be configurable under the full range of system resources.
5. When the card is accessed in DOS or Windows, but is not present, appropriate
messaging will occur.
Perkins believes SystemSoft meets the above criteria. However, one company's
solution may not be the answer, hence New Media continues to work with the
PCMCIA standards-setting committee to formulate an industry-wide solution.
While improvements in the specification are ongoing, they are redundant if
companies do not communicate effectively. According to Steve Magidson, a
partner in Ordinal Associates, a marketing consulting firm, this factor is
crucial. More than any other factor, it is the industry's positive response and
cooperation in this regard that has driven PCMCIA to its present level of
popularity. Platform, card, and software vendors have, over the past six or
eight months, greatly increased cross-testing and verification of operability
of products. Compaq itself checked its PCMCIA port with 145 cards from
different manufacturers before releasing the Concerto portable.
This cross-checking has resulted in much-improved reliability, to the extent
that “. . .users have come to expect the card to work and are no longer
shocked when it does,” said Magidson. Contrary to the situation 8 months ago,
when a card doesn't work it is the computer itself and not the standard that
gets blamed.
Encouraged with this level of end-user confidence, the PCMCIA is continuing
efforts to improve and add to the standard–although compatibility will remain
a priority. Work is now going into a port that can handle 3- as well as 5-V
cards for lower power consumption (critical in portable applications). A
multifunction card port is also in the works.
With ever-spiralling computer performance demands, it is a given that the
PCMCIA would someday migrate from its 8- and 16-bit interface to a 32-bit
interface. This is definitely on the PCMCIA agenda. Such an interface would
allow the cards to communicate at up to 80 Mbytes/s.
–Patrick Mannion
CAPTION:.
to come
For more information on PCMCIA cards, call these companies or circle the
appropriate the appropriate reader service number.
New Media Corp.
Irvine, CA
Saundy Morrison Hill 714-453-0100
Ordinal Associates
Thousand Oaks, CA
Steve Magidson 805-494-3931
Personal Computer Memory Card International Association
Sunnyvale, CA
Tiffany Trinh 408-720-0107
Databook, Inc.
Ithaca, NY
Daniel Sternglass 607-277-4817
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