Ozmoo - A Z-machine interpreter for the Commodore 64


Thanks, I’ll try to understand all this.

92 \
94 ^
96 ‘
123 {
125 }
126 ~

124 and 125 seem to be the same characters.


Thank you!

None of these characters exist in PETSCII, so we can’t show them unless we embed a custom character set. What we can do though, is map them for output to similar-looking characters.

We have already done this for two characters, character 95 (underscore) and character 124 (pipe). The pipe-like graphic character is in fact located at code 125 in PETSCII, so yes, 124 and 125 are currently the same character when printed.

EDIT: Added mappings for these characters. I suggest you PM me if you have further problems getting French characters to work. Hopefully I can update the docs to make it easier for the next person giving it a go.


I noticed this guy was porting zeugma to the bbc micro and I was wondering if you guys were thinking of porting ozmoo to the beeb as well.

github.com/hexwab/zeugma (it’s 3 years since it has seen dev)


There are of course several possible future ports.

We have listed a number of alternate versions we might want to make, but haven’t discussed priorities.

There is a guy who has shown interest in porting it to the PET. The code is there, for anyone who wants to have a go at creating a Beeb version too.


I created a page to package Z-code games with Ozmoo for playing on a C64 (real or emulated):


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This is neat. I played around with this tonight, cutting ATS in half and then creating an image that spans two disks. I could only get it to work as a .z8. I guess it was too tight for .z5 even though it was under 256k.

The game does run a little slow, but it’s emulated and outputs a lot of text. The site works like a charm, and after watching the page do its stuff I don’t think that I could do it on my own.

Thanks for setting this up, I’d like to run my next game through this after it’s published.

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Looking good!

I would be interested to see your z5 file and your z8 file. As far as I know, there is no way to create a game that can compile to z5 but won’t wotk unless you compile it to z8.

Do both files work in other interpreters?

What language are you using?


I’m using Inform 6, but the .z5 came out at 255kb. It’s right on the cusp. When I compile to a .z8 it came out at 259kb. So they’re true to their size. Both work fine in Gargoyle. But I think it has something to do with the headroom of the .z5, I got it down to 253kb and it works fine now. Before it was corrupting something, so when I typed RUN it was gibberish.


Some news on Ozmoo:

We’ve added support for REU (Ram Expansion Unit), meaning that when you start a game, if you have an REU installed, you can choose to cache the entire game to the REU. It will take a bit longer to start, but you’ll never have to wait for disk access once the game has started.

Also, it means you can play games built for dual disk drive systems with just a single drive. I played Jigsaw.z8 (298 KB) yesterday, and it ran just fine.

There were a few different REU:s made by Commodore. However, there are better REU:s built into various carts, including the popular 1541 Ultimate II+.

In Vice, you can enable a virtual REU either through the Settings menu -> Cartridge/IO settings or using the commandline: “x64 -reu -reusize 512”

There is no new release of Ozmoo available yet, but you can get the latest code by downloading it as a zip file at https://github.com/johanberntsson/ozmoo , or you can use Ozmoo Online at http://microheaven.com/ozmooonline/


Also, Ozmoo Online just got support for using the two custom fonts which are included with the Ozmoo distribution.