TRS‑80.org


Dr. Dobb’s Journal

Dr. Dobb’s Journal was one of the longest running microcomputer magazines, lasting 33 years in print form. It was first published in January 1976 as Dr. Dobb’s Journal of Computer Calisthenics & Orthodontia with the subtitle “Running Light Without Overbyte”. The title of the magazine was eventually shortened to Dr. Dobb’s Journal.

The name “Dr. Dobb” didn’t refer to a real person but was created by combining the first names of Bob Albrecht and Dennis Allison, the founders of the magazine. The magazine was originally created to promote the concept of Tiny BASIC, a small but powerful BASIC interpreter that could be used on the new microcomputers such as the Altair.

Integrated Tape – The Cassette Gazette Page 12

The Cassette Gazette was a 1983 one issue advertising newsletter that was a joint production of Lemons Tech and KWIK Software. The Gazette described the products sold by the two companies, mixed in with operational advice and interesting facts about using cassettes with your TRS‑80. It appears to have been written by Wayne Lemons, the […]

Which Loader For You? – The Cassette Gazette Page 11

The Cassette Gazette was a 1983 one issue advertising newsletter that was a joint production of Lemons Tech and KWIK Software. The Gazette described the products sold by the two companies, mixed in with operational advice and interesting facts about using cassettes with your TRS‑80. It appears to have been written by Wayne Lemons, the […]

How Tape is Made – The Cassette Gazette Page 10

The Cassette Gazette was a 1983 one issue advertising newsletter that was a joint production of Lemons Tech and KWIK Software. The Gazette described the products sold by the two companies, mixed in with operational advice and interesting facts about using cassettes with your TRS‑80. It appears to have been written by Wayne Lemons, the […]

The Micromint E-Z Color

Micromint sold several products for the TRS‑80 that were based on designs that Steve Ciarcia had presented in his Ciarcia’s Circuit Cellar column in Byte magazine. The Micromint E-Z Color was a color graphics interface for the TRS‑80 Model I and Model III that was based on his August 1982 column. In addition to the TRS‑80 version, there were also versions of the E-Z Color sold for the S-100 bus and the Apple II.

The TRS‑80 version was available in two configurations:

The Radio Shack Expansion Interface

The Radio Shack TRS‑80 Model I had few options for internal expansion other than adding a maximum of 16K of internal memory. The external expansion possibilities were reserved for a device Radio Shack called the Expansion Interface.

The Radio Shack Expansion Interface plugged into the back of the Model I using a six-inch long cable and was designed to serve as a base for the TRS‑80 monitor. It provided:

Christmas 2008 issue of TRS8BIT newsletter

If you haven’t stopped by trs-80.org.uk lately, then you might not know that Dusty has released a new Christmas edition of his TRS8BIT newsletter. Among other things, this issue includes a Sudoku creation program converted to the TRS‑80 by Peter Phillips. If you’re interested, you can download the current issue or any of the seven other issues.

The CHROMAtrs

Probably the most popular of the TRS‑80 Model I and III color add-ons was the CHROMAtrs, introduced by South Shore Computer Concepts starting in 1982. It was available in several configurations:

  • a kit without case or power supply cost $99.00
  • a kit with case and power supply cost $129.00
  • a fully-assembled and tested unit cost $169.00

Each CHROMAtrs unit supported both the Model I or Model III and would work with either computer using the proper cable. The Model III cable would also work with the Lobo MAX‑80 with a few minor modifications.

The Percom Separator

The Radio Shack Expansion Interface added single-density floppy disk support to the TRS‑80 Model I. Floppy disks were a great improvement over cassettes. But many people reported problems with reliability, particularly when reading or writing lower disk tracks. CRC errors and locked out tracks occurred with disturbing regularity.

The Separator, sold by Percom for $29.95, fixed all of those problems. It provided a data separator with far higher resolution (16 MHz) than the separator used by the Expansion Interface (1 MHz). Good data separation was vital for isolating the clock and data pulses that made up a disk track.