Emulating All The TRS-80 Software

Even if you didn’t own a TRS-80, the widespread footprint of Radio Shack in malls meant that if you are old enough, it is a good bet you have seen one and maybe even played with one. The games were crude, but state-of-the-art for 1982. If you wanted business software, that was there too, just don’t expect much on any of the personal computers of the day. My old TRS-80 Model III doesn’t boot anymore and is waiting for me to find time to pull it apart. But it turns out you can run all those old programs with almost no effort. If you’ve experimented with emulators before, you know there are two major problems. First, you need to install the sometimes-fidgety emulator. Second, you need to find the software you want to run and probably convert it into some format the emulator will read. The website named The Big List of TRS-80 Software solves both problems.

You are probably thinking this doesn’t solve any problem because it is just a list of links to software. That’s a reasonable thing to think, but we think the website really needs a new name. There are 15,873 pieces of software on the site, although some of them are duplicates or multiple versions of a single program. You can download them in a format that is useful for some emulators or, in some cases, the original files. But here’s the kicker. You can also click to launch a virtual TRS-80 in your browser and start the program.

Sounds great, right? Well, for the most part, it is. However, some of the programs are finicky and don’t run well in the browser. There’s also the problem of finding the documentation, but you can’t have everything. If you want a quick run of a very common game from back in the day, try Flying Saucers.

A Tale of Two Emulators

The browser-based emulator is from [Peter Phillips]. If the program you want to run doesn’t work well in the browser, you might want to try trs80gp, a full-featured stand-alone emulator that can run the DMK files you can download from the list.

The trs80gp software can emulate just about every TRS-80 and variant including the Model II and MC-10 Color Computer. The emulator is simply amazing. It not only emulates complete systems with cassettes, floppies, or hard drives, but it can even emulate the terrible display you’d expect from a vintage 1980s computer.

The emulator can slow down or run at full speed. You can even have cassette audio output captured automatically on the PC. Unfortunately, one of my old favorites — Asylum — acts the same in both emulators. It starts up, asks you a yes or no question, and refuses to accept any keyboard input. Keyboard input works for other programs, though. Even the emulator’s on-screen keyboard (both of them have one) won’t put input into this and a few other programs I tried.

Trash-80 Wine

There is a problem with the stand-alone emulator, though. There are versions available that don’t require Windows. However, the website mentions that the Windows version has more features. It does, however, run under Wine. In my case, I installed it using Crossover Office, which is a paid version of Wine. I can confirm that it works great.

Computer-aided design circa 1981

If you find a program you want to try on the list, you can start with the AUTORUN link to run it directly in the browser. If you prefer, you can download the DMK file and mount it as a floppy on the stand-alone emulator. Some floppies are bootable, and others require you to use the second drive with a standard boot floppy in the main drive. Don’t forget, the drives are numbers in TRSDOS and most other TRS-80 operating systems. So DIR :1 will list the files on the secondary drive.

If things don’t work, you can try the DEBUG link. This lets you select if you want to boot under DOS Plus, LDOS, NewDos-80, or TRSDOS. Another option is to pick up the individual files. You can’t download these files directly from the table. Instead, you click on the file name, and a page will show you the file along with several options.

BattleTrek, one of many Star Trek clones for the TRS-80

You can pick a few options for emulating or downloading the program from that page. You can also show and download the program parsed as a BASIC file, a text file, a Z80 program, or a  few other formats. The “Hex File” option, as far as I can tell, actually means raw, not an Intel hex format file. You can even edit the program in place and emulate it if you like, although for machine language programs, that will be difficult.

If you want a few things to try in addition to the UFO game mentioned above, try Battle Trek, or try your hand at word processing (type SCRIPSIT at the prompt). Just be prepared to explore the disks, run a few things, and maybe Google some old user manuals.


Is all this practical? No way. But if you enjoy computer history, this is an easy way to poke around in what would have been a truly extensive software library in its day. Sure, a real TRS-80 would be even more fun. But it would also be a lot more work, not the least of which would be transferring media around.

Then again, you could build a clone. Or play with some other browser-based retro computers.

36 thoughts on “Emulating All The TRS-80 Software

    1. Level 1 basic had the best error messages. ‘What?, How? and Sorry?’ were all the information you needed.

      Almost NSA style debugging (legend: testing at the NSA doesn’t tell the coders what the bug is, just that there is one. Supposedly the coders fix an average of 5 bugs before finding the one the testers found.)

      Lets not forget the expensive interface, and the buffered cable, and the buffered cable with twisted wire mod.

      Also ‘Time trek’ (real time trek game)…where you never aimed at the Klingons, you moved till they were at 0 degrees. If they were in the left most row, you left and came back. Damn that game sucked.

      My Crapple ][ was still better then your Trash-80. They were all forgotten as soon as the Amiga showed.

  1. “but it can even emulate the terrible display you’d expect from a vintage 1980s computer.”

    Actually, it was NTSC that’s terrible.
    The monochrome standards RS-170 (US) and CCIR (Europe) were fine.

    Monochrome CRTs could display 80 columns and about 800 to 1000 TV lines.

    The actual visual quality depended on the CRT tube used and the electronics, of course. 🙂

  2. The keyboard was raw hardware; no dedicated controller. The CPU directly polled the keyswitch matrix. We used to run a “debounce” program to address the ROM keyboard poller’s issues with poor contact just as a switch closes. So, some software may have done its own keyboard polling and not quite recognise the emulator’s efforts.

    1. A *lot* of programs directly read the key matrix, especially games. Even BASIC code sometimes could be caught peek( )-ing into that 0x3800-0x3bff area. If the emulator didn’t emulate the keyboard matrix, there’d be a lot of titles that would exhibit problems.

  3. My first major hardware hack I got the nerve to try was piggy backing 1 x 1k static ram chip at add the missing bit to get lowercase. Latter on a got a new character generator chip that allowed lower case without needing to load a driver. It was 1979 and I was in 9th grade.

    1. I followed Usborne’s “How to Build Computer Controlled Robots”, built the robot and the interface card. Had to do some dead-bug wiring because my relays didn’t look like ones in the book. Never had the balls to plug it into my C64 in case I fried it. 13 year old me didn’t have the skills to test it properly before plugging it in! Now that the books are public domain maybe i’ll do it all again just for fun.

  4. I ran a TBBS (The Bread Board System – Phil Becker) for years on a TRS-80 and later added the external 5 Meg Hard Drive to run TDBS (The DataBase System), TIMS (The Integrated Mail System – Fido), and games. Glad to see it listed.

  5. Back in the day, a company in Sterling VA (Misosys? Roy Soltoff? Doing this from memory) created a program known as PC4 which emulated a number of business programs and a bunch of games. Unfortunately SuperUtility wasn’t one of them.
    Thank you for the link and post. Looking forward to checking it out and comparing results to my Model 4.

  6. Like they say, kids have no idea how tough it was, developing something awesome in a small computer, RAM was tiny, cassettes instead of disks and then later disks, “dots” were more like squares, but we still used them effectively to do stuff in the 80s.

  7. I have some cassette based programs that I would like to resurrect. Do any of these emulators work well with doing that? I assume I would have to connect a cassette player output to the PC sound card input, correct? Then how would I resave them so I would not have to reload from cassette each time.

    If this is covered somewhere on one of the repository sites, can someone point me in the right direction?


      1. The programs are a series of programs I wrote for teaching my high school physics classes, they are not commercial programs.

        I used them on e cassette based model 1.

        It is not “important” that these programs be resurrected, it would just be a nostalgia thing.

    1. Oooooh… how old are the cassettes? Bit rot may have set in. I lost many old floppies that way.

      If you can connect the tape player to the PC’s mic-in port and capture the cassette contents as .WAV files, .WAV-to-TRS-80-.CAS software can convert them to an emulator-friendly format.

  8. There are many versions of Model I Asylum II out there that were ripped from cassette and had their loading addresses changed to work on disk systems. Some of these work on Model IIIs while some suffer the keyboard lockup issues. This may be true also for Asylum, but I dunno. Maybe try to find a different version.

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