The Patch was a unique all-hardware approach to implementing lower case on a TRS-80 Model I. It was sold by CECDAT Inc. for a price starting at $69.97.
The normal approach to adding lower case involved a hardware modification plus a software driver. Radio Shack never added a lower case driver to the Model I ROM, so the separate driver was required to enable generation of lower case characters. The lower case driver was stored in RAM, so it needed to be loaded again from cassette or disk every time the Model I was used.
The Patch combined an ordinary lower case hardware modification with a “patch” to the Model I ROM that added a lower case driver. Probably the best description of how it worked comes from one of their advertisements:
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I was saddened to learn that Irvin Mike Schmidt passed away on February 16, 2009. Usually credited as I. Schmidt or Mike Schmidt, he was the founder and driving force behind 80-U.S. Journal, the TRS-80 magazine that he published from 1978 to 1984. He was the editor-in-chief for most of its run and his influence was very evident in the magazine.
You can read an obituary for him here.
80-U.S. Journal was the best remembered name for a TRS-80 magazine that was published by 80-Northwest Publishing from 1978 to 1984. It was also published under the names 80-Northwest Journal and Basic Computing. Until 1982, it was published bimonthly (six issues a year) but it increased to monthly (twelve issues a year) after that.
80-Northwest Journal (sometimes called 80-NW Journal) was first published in 1978 with the September/October issue. The founder of the magazine, Irvin “Mike” Schmidt, described the reason behind the new publication in the first issue:
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The TRX-280 was a proposed motherboard replacement for the TRS-80 Model 4, described in the December 1990 issue of Computer News 80 and issue 38 of TRSLINK. It was created by Peter Ray of Anitek Software Products in an attempt to design a “next generation” TRS-80.
The TRX-280 design was based around the Z280, an enhanced Z80 compatible processor created by Zilog. The Z280 was an interesting chip, providing software compatibility with the Z80 yet adding many new features, such as a memory management unit, new addressing modes, and new instructions. It was also faster than the Z80 at the same clock speed.
The TRX-280 was planned as a drop-in replacement for the Model 4 motherboard (and possibly the Model III as well). It would have remained compatible with all TRS-80 software and hardware, with the one exception that it would have lacked a cassette port.
The TRX-280 had an impressive set of proposed features:
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The LNW System Expansion was a popular alternative to the Radio Shack Expansion Interface. Introduced in 1979 by LNW Research, the System Expansion was the most popular of the Expansion Interface replacements. LNW Research later described themselves as “the number one manufacturer of system expansion units and accessories for the Model I computer”.
The LNW System Expansion sold for $69.95 as a kit with a bare printed circuit board and manual. LNW later introduced the $399.95 LNW System Expansion II, which provided the same features but came assembled in a metal case.
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The Color-Graf was a color graphics interface for the TRS-80 Model I and Model III. Sold by Solectronics, the Color-Graf originally cost $260.00 for the Model I version. That price was later reduced to $195.00 for the Model I version and $235.00 for the new Model III version. Solectronics advertised the Color-Graf from 1982 to 1983.
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80 Microcomputing, later 80 Micro, was the most popular of the TRS-80 magazines. It was ranked the seventh fastest growing magazine in 1982 and was the third thickest magazine that year. (Those figures were for all magazines, not just computer magazines.)
80 Microcomputing began publishing in 1980, and its circulation rose steadily until it topped 124,000 readers in 1983. Circulation began a slow decline after that although subscriptions picked up slightly in 1985.
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Back in 1983, Lemons Tech and KWIK Software advertised a one issue joint newsletter named the Cassette Gazette. The Cassette Gazette described the products sold by the two companies, mixed with operational advice and interesting facts about using cassettes with the TRS-80. It appears to have been written by Wayne Lemons, the founder of Lemons Tech. I received my copy back in 1983, and it has always been a favorite of mine.
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Jack Crenshaw has a long history with computers, and one of his first microcomputers was a TRS-80 Model I. Readers of 80 U.S. Journal might remember his comments about the Exatron Stringy Floppy. Others will remember his “Let’s Build a Compiler” tutorial series. His “Programmer’s Toolbox” column appears in Embedded Systems Design magazine, for which he is also a contributing editor.
This interview was conducted over January and February 2009.
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“The Next Step” was a popular column written by Hardin Brothers that began in the February 1983 issue of 80 Micro. Originally conceived as a five part column about integrating BASIC and assembly language, “The Next Step” went on to become one of the longest running columns in the magazine.
The focus of “The Next Step” was programming the TRS-80 in assembly language. It covered the Model I and Model III at first, but had largely switched to the Model 4 by 1984. The name was a reference to assembly language as being the next step beyond BASIC, as was stated in the first column:
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