What interface cards are incompatible with the PDS expansion slot in the Macintosh 630 family of computers?

While the I/O expansion slot will accept PDS cards designed for the Macintosh LC II and LC III, some of those cards do not work. Cards that are incompatible with the PDS expansion slot include:

* Cards designed to work as coprocessors with an MC68020 or an MC68030 or as replacements for those microprocessors. Such cards include accelerators, 68882 FPU cards, and cache cards. That type of card won't work because the microprocessor is different and because the slot signals are not connected directly to the microprocessor.

* Cards with drivers that include incompatible code. Some drivers that do not follow Apple Computer's programming guidelines won't work on machines that use the MC68040 microprocessor. For example, some of those drivers write directly to the cache control register in an MC68030. Such code won't work on an MC68040.

* Cards with drivers that include code to check the gestaltMachineType value and refuse to run on a newer CPU. The idea is to protect users by refusing to run on a machine that the cards haven't been tested on. Such cards have compatibility problems with all new Macintosh models.