A Z-Machine Interpreter for Palm

Adventure Screenshot    

FAQ Logo


6 January 2004: Frobnitz 1.02 released. Fixes the improperly mapped sz-ligature character and updates URLs.
15 November 2003: Launched next generation project on SourceForge
6 February 2001: Frobnitz 1.01 released. Updated color detection for compatibility with Backdrop GC.
8 January 2001: Frobnitz 1.0 released.


Frobnitz is a Z-Machine interpreter that runs on PalmOS. What's a Z-Machine, you ask? It's the virtual machine developed by Infocom for its text adventures, also known as "interactive fiction". Infocom has long since passed on, but the Z-Machine format has since been adopted for the authoring of interactive fiction by others.


Frobnitz supports the following:


To usefully run Frobnitz, you will need the following:


Bureaucracy Screenshot     Beyond Zork Screenshot

Frobnitz running Bureaucracy on a Palm V. Yes, all of the form-drawing and cursor-positioning logic works properly.

    Frobnitz running Beyond Zork on a Palm IIIc. Note the support for color. Tapping an exit on the map (not shown) will register as a move in the game.


Name: Frobnitz 1.02

Software that you install to your Palm device and a file converter so you can install story files. Includes an adaptation of the original Colossal Cave Adventure, already converted to a Palm database (.PDB) file for your convenience.

Download: (117K)


The Interactive Fiction Archive

The definitive archive of all things IF. The original is hosted at the GMD in Germany The web mirrors should be faster for most visitors. from the United States. Of particular interest will be the section devoted to Z-Machine adventures; you can run every game there on Frobnitz except those ending in ".z6".


XYZZYnews, the magazine for interactive fiction enthusiasts.


A yearly competition for short text adventures.

Unofficial Infocom Homepage

Definitive Homepage to pay homage to the company that created some of the best computer games. You can download Zork I, II, and III from this site.

Inform: A Design System for Interactive Fiction

If you want to write games that can be played with Frobnitz (or any Z-machine) you need to get Inform. A fantastic compiler suitable for anyone to learn to use.


Does Frobnitz support Palm OS 5?
Frobnitz will run without causing any serious problems on Palm OS 5. However, there are some display glitches with the cursor. Also, a few devices generate wonky keypress codes which render the scrollback useless.
I found a bug in V1.02. What now?
Frobnitz has been downloaded nearly 20,000 times over three years. In all this time the only true bug found was an incorrectly mapped sz-ligature character. We're aware it's not compatible with some hacks, storage in ROM or on removable media, and Palm OS 5 (technically, all features). The V1 code is retired and a new version is in the works. All you can do is learn to live with the problem and await a new release.
What's the difference between Pilot Zip, Pilot-Frotz and Frobnitz?
Pilot Zip is very old shareware, and is all but lost forever. Pilot-Frotz is a freeware Z-Machine interpreter for the Palm platform written by Paul Margrave. All three programs attempt to solve the same problems, but go about it in different ways. You should feel free to try both Pilot-Frotz and Frobnitz and use the one you like best.
What does the word 'Frobnitz' mean?
Nothing, really: it's a bit of hacker lore that originated at MIT decades ago, and was incorporated into several of the Infocom titles by the company's programmers, most of whom were MIT alumni. See the corresponding entry at for further details.
Where can I get those great games published by Infocom?
Infocom and rights to all of it's games (except Hitchhiker's and Shogun) was bought by Activision. For a while they were selling all the Infocom games on CD collections, but no longer as far as I can tell. Searching eBay for the word 'Infocom' seems to be a good approach. Fortunately, you can download Zork I, II, and III from a fan site.
I used z2pdb to convert a story file and Frobnitz reports an error when I try to run it?
That source file isn't the right kind of story. Games often exist as "disk images" so they can be run on emulators. Most likely you have a C=64 or Apple ][ disk image. Try playing the original file in a desktop version of Frotz or Zip and see if it runs there.
How do I convert a PDB file that was made for Pilot Frotz or Pilot Zip?
You don't have to. Whenever Fronbitz is launched it searches all the databases for Frotz and Zip style stories and converts them automatically. However, if Pilot-Frotz or Pilot Zip is installed on your device it won't convert their databases automatically.
I'm not ready to give up Pilot-Frotz yet. Can Frobnitz use the Frotz databases?
Yes, but I can't promise it will work perfectly. At the screen where all the games are listed (or where it says "No Games Installed") you enter the magic word "BORROW". You won't get any indication of text being entered until you enter the whole word without error. If you do it sucessfully, the screen will refresh and all files of type 'ZCOD' will be displayed. This setting will be retained until you reset your device. I made this difficult on purpose so that you know you are doing something that might not work perfectly.
I am ready to give up Pilot-Frotz and Pilot-Zip. Can I steal their databases before I delete them?
Yes, read the previous question and use the magic word "STEAL". You will be prompted asking if you really want to do this. Note that only the story files will be converted, your save games are not converted.

Valid XHTML 1.0!   Valid CSS!