1980s Vintage Computers

Cromemco Z-2D

This large box introduced in 1979 was a well engineered example of a typical S-100 bus machine of the CP/M era. It is built in a strong steel case with a high-current power supply feeding a 21-slot bus. However this is rather a waste as this machine only has 4 cards! As they were so well built a lot have survived to the present day so they are quite common. I was lucky in that I was given this machine together with an ADM-3A terminal and Anadex printer. 

My System Two machine has four cards, all made by Cromemco and all in good condition.

  • Cromemco ZPU containing a Z80 processor.
  • Cromemco 64KZ memory card containing 64KB of RAM (bank switchable).
  • Cromemco PRI providing two parallel ports.
  • Cromemco 4FDC floppy disk controller. This also contains the RDOS boot EPROM, which has some basic monitor commands, and a serial port for a terminal.

I was kindly sent a CDOS disk for this machine by a fellow collector in the UK. However I have not yet been successful in finding a CP/M disk, the key requirement is that it runs on a 4FDC card (an image file is available for the 16FDC version).


Cromemco machines have been popular with collectors, and there are several sites that feature them:


Various Cromemco systems and manuals at Daves Old Computers

Here are some photos of my machine, it is an impressive box compared to the more common plastic cased machines:

Update: I sold my Z2D and ADM 3A in 2010, the terminal was shipped to Germany, and the Z2D went to Jim Austin's collection.






This page was last revised on: 23/12/14