Matthew Reed's TRS-80.org


The MicroMerlin

The MicroMerlin (referred to in some advertisements as the ĀµMerlin) was a MS-DOS compatible add-on for the TRS-80. It was released by Micro Projects Engineering in 1982 with a starting price of $1,195.00.

The MicroMerlin connected to the expansion bus of a computer and required no hardware modifications to the computer itself. It originally supported the Model I and Model III, but later also the Model 4 and LNW80. There were two hardware requirements:

Deathmaze 5000

Deathmaze 5000 was the first of the “Continuum Series,” a set of 3-D adventures sold by Med Systems Software. The other games in the series were Labyrinth, Asylum, and Asylum II. In addition to the TRS-80 version of Deathmaze 5000, Med Systems also sold both tape and disk versions for the Apple II.

Deathmaze 5000 has many similarities to Rat’s Revenge, an earlier Med Systems Software game also written by Frank Corr. Both games feature a 3-D view with the player using arrow keys to move through a maze. Unlike Rat’s Revenge, which focuses on finding the cheese within a maze, Deathmaze 5000 falls somewhere between an adventure game and puzzle.

Encyclopedia For The TRS-80

Back in 1981, the TRS-80 was the best selling computer and 80 Microcomputing magazine was bursting at the seams. Wayne Green, the publisher of 80 Microcomputing, envisioned a new set of books: the Encyclopedia for the TRS-80. As the first advertisement for the Encyclopedia stated:

Model I TRSDOS Versions

TRSDOS 2.0 was the first version of Model I TRSDOS to be released to the public. All earlier versions had been used for testing within Radio Shack only. It came with a preliminary instruction manual, with a final manual promised for the near future. Not many people used TRSDOS 2.0 because it was replaced by TRSDOS 2.1 after only a short time.

Model I TRSDOS Disk BASIC Commands

Model I TRSDOS Disk BASIC contained a number of extra commands and enhancements to Level II BASIC, not all related to disk. The commands were documented in the TRSDOS 2.3 Reference Manual. All other TRS-80 operating systems with a Disk BASIC supported these commands, although often CMD and NAME used different syntax.

Model I TRSDOS Commands

The Model I TRSDOS command shell supported a number of internal commands, as documented by the TRSDOS 2.3 Reference Manual. Most of the commands were also supported by other TRS-80 operating systems, although they usually added extra features beyond the TRSDOS versions.

TRSDOS for the Model I

TRSDOS, referred to as DOS in some early references, was Radio Shack’s official disk operating system for the Model I. The name stood for Tandy Radio Shack Disk Operating System. It was bundled with Radio Shack’s floppy disk upgrade, but it could also be purchased separately.

Was the Model I ever sold as a kit?

Some have claimed that Radio Shack offered the Model I as a kit before selling it as a fully-assembled computer. That is not true. From the very beginning, the TRS-80 was sold only fully assembled and there was never a TRS-80 kit option in any Radio Shack catalog.