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MITS - 8080 CPU
This board has the distinction as being the first S-100 board ever designed.  The layout of the board with its pinout from the 8080 CPU essentially defined the function of the S-100 bus pins.

 Altair 8080 CPU   

This board looks primitive by today's standards but it should be remembered that then some minicomputers did not have gold plated edge connectors.  The CPU was clocked at 2MHz. It utilized Intel's 8212 chip to define a number of the "Altair" bus lines. The only other significant component on the board was a Molex connector to allow a connection to the computers front panel switches. These allowed the CPU to be single stepped, programmed etc.  Note the relatively scarcity of plated through holes on the board. The shortest route traces to the 100 pin edge connector defined the bus signals.  Unfortunately this layout was not optimum from a signal noise perspective. However the good news was that there were many unused connectors pins that later allowed the bus to be extended to complex 16 bit CPU systems and the IEEE-696 format.
There was no separate manual for this board. The relevant pages from the Altair Computer Kit manual can be obtained here.  They are included here to show the detail that was supplied in constructing the Altair Kit. 
The schematic for the board can be obtained here


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This page was last modified on 10/25/2013