David Cook
Well-known member
Does anyone know of technical documentation for the Apple Communication Slot interface present in the LC/Performa 575 series, Quadra/Performa 630 series, and early PowerPC models? The most I've found are pinouts and some current draw / compatibility information:
Some of the pins are obvious, such as +5, GND, TX, RX, and handshaking. But, many of the other pins seem interesting but need more explanation.
My goal is to design a diagnostic card that measures voltages, checks for CPU activity, and so on. It would then report the information through the serial pins to some software that could graph or record it. I figure the communication slot is great first step project because it doesn't need a special connector, PALs/GALs, parallel interface, driver resources in ROM, or even anything fancier than a microcontroller. After that, I can step up to the PDS slot or maybe NuBus.
Some of the pins are obvious, such as +5, GND, TX, RX, and handshaking. But, many of the other pins seem interesting but need more explanation.
My goal is to design a diagnostic card that measures voltages, checks for CPU activity, and so on. It would then report the information through the serial pins to some software that could graph or record it. I figure the communication slot is great first step project because it doesn't need a special connector, PALs/GALs, parallel interface, driver resources in ROM, or even anything fancier than a microcontroller. After that, I can step up to the PDS slot or maybe NuBus.