With the number of PC-compatible workstations growing, questions have
arisen concerning the compatibility of these workstations with the
LocalTalk PC card and AppleShare PC. This article describes the issues
surrounding the card.
Bus Speed
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Most PCs or compatibles have an 8 MHz bus. Some compatibles run their
buses at a faster rate and have a mode to slow the bus speed. Those that
do not have this slower mode find a great many cards are not compatible,
because most cards are designed for compatibility with the IBM-PC 8MHz bus.
The LocalTalk PC card has been tested successfully for 8-MHz compatibility.
However, faster bus speeds produce reports of incompatibilities.
DMA
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The LocalTalk card works with either DMA channel 1 or 3. One of these
DMA channels must be present and available on the PC or compatible.
Control Signal Address Ranges
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The LocalTalk card uses the address ranges $240-$247 or $220-$227. One of
these ranges must be available.
Software Compatibility
----------------------
AppleShare PC is compatible with most software. Some packages, while
running, don't allow the DA pop application to appear. These packages are
capturing either the keyboard command or holding the operating system in a
state where the DA cannot appear. In these cases, the DA usually sounds a
beep. The only method of using the DA is to set up connections or make
configuration changes in the DA prior to running these applications.
Also, some printer utilities reroute the printer ports for spooling,
buffering, or emulation. These may not work with AppleShare PC, may cause
problems, or may even cause the PC to hang.