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Cromemco 8PIO   
This is an 8 port parallel I/O port board. It was a natural evolution of their 4PIO board.

Cromemco 8PIO

Each of the eight independent I/O ports consists of a separate input port and an output port with the same port address. Each input/output port pair share 8 bidirectional lines which are brought out to EIA connectors (J1 thru J4) for I/O interfacing. Both the input and output ports are latched: output data is automatically latched into an OUT port when the system CPU executes an output instruction to the 8PIO.  Input data is latched into an 8PI0 IN port by a positive going transition on the LATCH INPUT line which is controlled by the user. Handshake signals are provided on both the IN and OUT ports.
I/O port number 6 plays a special role on the 8PIO. It may be left in its factory wired condition to software monitor and control the other seven 8PI0 ports, or alternately, it may be reconfigured as a standard eighth I/O port. The 8PI0 provides three onboard terminal I/O devices:  an  8-bit   switch  register, a 3-bit switch register and an 8 LED display register. The 8PI0 also features four versatile interfacing circuits: a pair of OUT port activated relays and a pair of optically Isolated couplers connected to an IN port. All of these devices are connected to the SPIO In a non-dedicated fashion: they may be either used or left unused in a way that leaves ail ports available for I/O with other devices .
The manual for this board can be obtained here


Other Cromemco S-100 Boards
ZPU  SBC   4KRAM  16K RAM  64KZ RAM  64KZ-II RAM  256KRAM  8KBytesaver  Bytesaver-II  
16KPROM  32K Bytesaver  4FDC   16FDC  64FDC  WDI  WDI-II   STDC   DPU
4PIO   8PIO   TU-ART  D+7A I/O   Dazzler  PRI   GPIB Board   XMU  XXU  Other Boards


This page was last modified on 10/25/2013