When a Minicomputer becomes a Micro: the DGC microNOVA mN601 and 602

The late 1960’s and early 1970’s saw the rise of the mini-computer.  These computers were mini because they no longer took up an entire room.  While not something you would stick on your desk at home, they did fit under the desk of many offices.  Typically there were built with multiple large circuit boards and their processor was implemented with many MSI (medium scale integration) IC’s and/or straight TTL.  TTL versions of the 1970’s often were designed around the 74181 4-bit ALU, from which 12, 16 or even 32-bit processor architectures could be built from.  DEC, Wang, Data General, Honeywell, HP and many others made such systems.

By the mid-1970’s the semiconductor industry had advanced enough that many of these designs could now be implemented on a few chips, instead of a few boards, so the new race to make IC versions of previous mini-computers began.  DEC implemented their PDP-11 architecture into a set of ICs known as the LSI-11. Other companies (such as GI) also made PDP-11 type IC’s.  HP made custom ICs (such as the nano-processor) for their new computers, Wang did similar as well.

Data General was not to be left out.  Data General was formed in 1968 by ex DEC employees whom tried to convince DEC of the merits of a 16-bit minicomputer.  DEC at the time made the 12-bit PDP-8, but  Edson de Castro, Henry Burkhardt III, and Richard Sogge thought 16-bits was better, and attainable.  They were joined by Herbert Richman of Fairchild Semiconductor (which will become important later on.)  The first minicomputer they made was the NOVA, which was, of course, a 16-bit design and used many MSI’s from Fairchild.  As semiconductor technology improved so did the NOVA line, getting faster, simpler and cheaper, eventually moving to mainly TTL.

Read More »