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CompuPro - CPU 86/87
This was CompuPro's main 8086 CPU board. While the CPU 85-88 allowed easier transition from 8 to 16 bit software it was slower than this fully dedicated 16 bit processor.

CompuPro CPU 87-87

The CPU 86/87 was one of the most advanced 16 bit processors available for the IEEE 696/S-100 Bus. Based on Intel's high performance 8086 16 bit processor, it also included sockets for the 8087 high speed math co-processor and the 80130 Operating System Firmware component. Via a special arrangement with Intel, CompuPro supplied this board with a "ROM-less" version of the 80130 so that the user may retain full use of that part's interrupt and timer capabilities without paying for software that probably would not use. The CPU 86/87 however was designed to accept the ROM part should it be needed. The CPU 86/87 included circuitry that allowed it to handle 8 and 16 bit memory and I/O devices that conformed to the IEEE 696/S-100 protocol for 8 and 16 bit transfers. Both 8 and 16 bit types could be mixed in a system, the CPU 86/87 dynamically adjusted itself to the proper bus width. The CPU 86/87 was fully compatible with DMA devices that adhere to the IEEE 696/S-100 standard protocols (like CompuPro's DISK 1A, DISK 2, DISK3 etc.).
The CPU 86/87 operated at 8 and 10 MHz clock speeds, but was designed to accommodate faster clocks as faster CPUs as they were introduced. A special clock switching circuit allowed the use of specially designed slave processors to share the bus with the CPU 86/87. Use of an 8 bit slave CPU provided the equivalent operation of their CPU 8085/88 dual processor board, thus providing a simple way to execute libraries of existing 8 bit software, as well as CompuPro's exclusive  MP/M 8-16. The CPU 86/87 included power-on-jump capabilities that allow it to begin program execution on any 4K boundary in the lower 1 megabyte of address space. When you couple high speed operation with the power of the 8086/8087 pair, the CPU 86/87 was truly a processor board for the advanced computing systems of the early eighties. BTW, the seldom used front panel connector was finally gone.
The manual for this board 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