D-G Electronic Developments Co., Inc.



  • D-G Heartbeat Computer
  • D-G Super 89 CPU board
  • H8 static and dynamic memory boards
  • H8 Z80 CPU board

Software - Operating Systems

  • DG CP/M Plus
  • DG MP/M II

Personal Collection

I recently bought a H89 on ebay which contained the D-G Super 89 CPU board (along with an Cleveland Codonics Imaginator). The system was in poor condition and needs major cleaning and repair. I plan to have pictures and more details shortly.

I would love to get copies of both the DG CP/M Plus and DG MP/M II operating systems. 

Company Status

Unknown, assumed dissolved.

Last Modified: Wednesday, 16-May-2018 20:14:08 PDT

Contact Details

Mark Garlanger

Email: mark [at] garlanger [dot] com

If you email me, PLEASE check your spam filter for any responses.

Website: www.garlanger.com


This site is dedicated to preserving the history of the original Heathkit computers. They were initially release in 1977 and included the 8-bit H-8 and 16-bit H-11 systems. The H89 was released in 1979.