TRS-80 Emulator for Mac OS

version 1.6 (7/11/99)

TRS-80 screenshot

NEW: The TRS-80 Emulator for Mac OS forum.

TRS-80 Emulator for Mac OS (v1.6)


The emulator is now Mac OS 8.5 aware.


This is a complete re-write of the application to CFM specs. It is compiled fat and runs native on PowerMacs (it requires CFM-68K on 68K based machines). The emulation engine, however, is still written in classic 68020 assembly language and runs emulated on PowerMacs.
The emulator supports the Appearance Manager when present (Mac OS 8 only).
The main window has icons for the drives, a reset button and an NMI button.
Clicking a drive icon when the drive is empty will prompt you to insert a virtual floppy disk, clicking it when the drive is not empty will eject the virtual floppy. Dragging a virtual floppy to a drive icon will insert it into the drive (ejecting whatever disk may already be there).


Clicking the zoom box doubles the screen size.


The emulator now has two 80-track virtual floppy drives (was one 40-track drive in v1.0).
The documentation has info on using ".DSK" files.

A BIT OF HISTORY (version 1.0):

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).


- For Power Macintoshes:

System 7.5.5, System 7.6.1, Mac OS 8.1, Mac OS 8.5 or greater.

- For Macintoshes:

68020 or later.
System 7.5.5 or greater (Mac OS 8 recommended).
CFM-68K Runtime Enabler (built-in System 7.6.1 or greater).


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.

Downloading the TRS-80 Emulator:

The emulator can be downloaded using either MacBinary (.bin) or BinHex (.hqx) format.

You can also download the emulator from

Downloading the games only:

For those of you who do not have a Macintosh but would like to play my games on some other emulator, here they are in .DSK format.

For info about the TRS-80, check out The TRS-80 Home Page.
For TRS-80 software, check out Ira Goldklang's TRS-80 Revived Pages.

Something I found on the net: Emulation as a Form of Flattery

Back to my Home page.

Made with a Mac SAX All contents copyright © 1995-2011 Yves Lempereur, all rights reserved.
Revised: 12 Apr 2011