Sunday 8 March 2015

35 years old Arduino-like setup with Pascal

I do not care much about products or constructions from the past, that cannot be reproduced or used, but in this case, my brother's old construction from the late 1970s made me look again, because it looks so much like what people do with Arduino kits.

This is a computer programmed using Compas Pascal or Turbo Pascal:



Specs:

  1. CPU: Zilog Z80, of model Z80CPU01. This is probably running 1-2MHz. The Z80 was an extended version of the 8080 CPU, on which the 8086/8088/Intel CPU line of CPUs was built.
  2. One EPROM for the runtime
  3. One EPROM for the actual program
  4. 5x4 keyboard on the back, suitable to be used as a 4x4 hex keyboard with some more keys.
  5. Some RAM chips etc.
  6. I/O pins for easy access.
Unlike today, where we can program Arduino boards etc. using flash, easily, that kind of technology was unavailable or extremely expensive. Therefore, EPROMS were used, which could easily be erased using an ultraviolet lamp, and easily re-programmed using this board, which used the Centronics port for I/O to the programmer's computer, as USB was not invented back then.

 
The main computer, that was used for programming, could be a Zilog Z80 Nascom computer, a CP/M-80 computer, or any homemade computer that was using a 8080 or Z80 CPU.

Compas Pascal and Turbo Pascal were obvious choices for this, as the compiler was fast and generated great code, and therefore boosted programmer productivity a lot.