Posts tagged with “CP/M”

The Freedom Option

The Freedom Option was a CP/M add-on for the TRS‑80 Model I, Model III, and compatibles. It was introduced in early 1980 by Field Engineering Consultants (better known as FEC) of Woburn, Massachusetts.

Originally, FEC sold two Freedom boards, both for a 48K Model I with disk drives:

The Freedom Option allowed CP/M (or the included T8/OS) to run by disabling the Model I ROM. It cost $245.00.

The Hurricane Labs Compactor

The Hurricane Labs Compactor was part of a series of products that modified the TRS‑80 Model III to allow it to run CP/M programs. Hurricane Laboratories, better known as Hurricane Labs, was founded by Ronald L. Jones, a member of the Homebrew Computer Club who had a great deal of experience with CP/M.

There were three Compactor products for the TRS‑80 from Hurricane Labs, all designed by Ron Jones:

The Compactor I, introduced in late 1981, sold for $450.

The Shuffleboard

The Shuffleboard and Shuffleboard III were CP/M hardware add-ons for the TRS‑80 Model I and Model III. Although somewhat different products, each allowed unmodified CP/M programs to run on the TRS‑80 by “shuffling” the TRS‑80 memory map into one acceptable to CP/M.

Both the Shuffleboard and Shuffleboard III were created by Parasitic Engineering, but the Shuffleboard III achieved most of its popularity after Memory Merchant took over the product.

The Omikron Mapper

The Omikron Mapper was the first (and probably most popular) CP/M hardware add-on for the TRS‑80 Model I and Model III. It allowed unmodified CP/M programs to run on a TRS‑80, something not normally possible. The Omikron Mapper was introduced in 1979 by Omikron Systems, a Berkeley, California company run by George Gardner.

Omikron Systems sold three versions of the Omikron Mapper from 1979 to 1984:

The original Omikron Mapper I was for the Model I.

The Holmes VID-80

The Holmes VID-80 was a popular add-on for the TRS‑80 Model I and III. Introduced by Holmes Engineering, Inc. in 1982, the VID-80 offered two related features:

It expanded the TRS‑80 screen from 64 characters wide by 16 characters high to the larger 80 characters wide by 24 characters wide.
It changed the TRS‑80 memory map to allow running the CP/M operating system.


BIGMEM was a modification for the TRS‑80 Model I which increased available memory. It was introduced by Microhatch in early 1982 for $180.00, but the price was reduced to $169.00 by late 1983. Microhatch also sold a utility disk (with print spooler) for $20.00 which could be bundled with BIGMEM. For any user unwilling to perform the modification, Microhatch would install BIGMEM for $199.00.