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CompuPro - 68000 CPU
This is a difficult CompuPro (actually Viasyn) board to now find. It was used for the development of CPM-68K software when it was thought that that was the direction future microcomputer software was going to go in the early 80's.  Clearly it did not happen.  Nevertheless the board is quite something and worth maintaining.  The board was introduced in April 1983.


The board normally ran with an 8 MHZ clock with some 10 MHZ versions. (Remember the clock in 6800x chips was ~2X the Intel chips). The two empty sockets could accommodate 2716, 2732 or 2764 EPROMS in a high/low byte arrangement.

The challenge for Motorola CPU's was there was no separate I/O signals. CompuPro mapped the 256 I/O ports to addresses FF0000H to FFFFFFH. Only the lower 8 bits were normally used.   One unusual thing about the board was CompuPro allowed the S-100 master clock signal (#24) to be disabled by a signal on pin 21. This allowed slower slave processors to run on the bus at a lower speed.  The board also allowed up to 5 wait states be put on the bus.

The 68000 had a built in seven level priority interrupt structure this made splicing it to an external interrupt controller on the bus a little tricky. CompuPro provided a few options on this board.  There was a large empty socket in the center of the board that was used to add an optional 68451 memory management chip.

The schematic for this board can be obtained here.  The technical manual can be obtained here.


Other CompuPro S-100 Boards
CPU8085-88  CPU86-87  CPU-Z  Disk1  Disk1A  Disk1B  Disk2  Disk3   EconoROM2708  Interfacer 1  
RAM Boards   Interfacer 3  Interfacer 4   Interfacer II   M-Drive  MPX-Board  PC-Video  
System-Support1  System-Support2   SPIO  Spectrum  SP186   CPU-286
   68000  32016  SPUZ


This page was last modified on 10/25/2013