The IMSAI MPU-A 8080 CPU card was
what the original Altair equivalent card should have been. It was
made on a better quality board with proper gold plated edge connectors and a
cleaner well spaced trace pattern. Clearly resistor packs were still not that
common and nothing but the absolute essentials to put the 8080 signals on the
bus were present. It was meant to be a direct copy of the Altair board although
it did use a 16 pin connector on the top right hand corner to interface to the
front panel instead of Altair Molex connector. Clock and strobe signals were
generated by a 8224 clock driver.
The manual for this board can be
obtained
here.
The schematic can be see
here. Its interesting to see how simple this board is. The S100 bus was
really at the start just an 8080 bus!
