by Yves Lempereur
"Back in 1982, I used to work for a software publisher called Funsoft, Inc. At the time, I was writing games for the TRS-80 Model I/III. In '83, I wrote games for the Atari 400/800. In '84, I started to write software for the Apple Macintosh, which is what I still do today.
"In 1990, I'm not exactly sure why, I decided to write a TRS-80 emulator for the Macintosh (I guess I wanted to play some of my games again). I didn't have a TRS-80 anymore, so I got one on loan from a friend (thanks Mike). I gathered all the information I needed (getting the specs on the FDC directly from National Semiconductor wasn't the easiest part) and started to code. Three months later, it was done. It ran the BASIC ROM, DOS and all my games (as well as many others).
"I wanted to put it in the public domain, but I was worried about the fact that it contained a copy of the TRS-80 ROM's. I stashed it away somewhere on my hard drive and promptly forgot about it. Six years later, about a month ago, I received an e-mail from John Stiles (who has an "emulation for the Macintosh" page on the web) telling me that somebody had told him I had written a TRS-80 emulator, which was never released, and asking me if he could distribute it.
"I just spent the last three weeks cleaning it up and getting it ready. I'm still worried about copyright issues, but I'm hoping that since TRS-80's haven't been sold for over a decade and I'm not trying to make any money out of the emulator, nothing bad is going to happen to me (crossing fingers). "
The TRS-80 emulator simulates a TRS-80 Model I with an Expansion Interface, two 5" floppy drives and 48K of RAM. It does so by emulating the hardware, not by intercepting OS calls. This is less efficient, but much more compatible. The Z80 and hardware emulations are written entirely in 68020 assembly language, the application interface is written in C.
TRS-80 Emulator for MacOS [Homepage]