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Joust prototype ROM recreated

Thomas Jentzsch

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I was a bit bored today, so I downloaded some original source code from the Atari 2600 Connection website. The Joust code was from July 5th, 1983 and I couldn't find the ROM anywhere (though it is mentioned at AtariProtos.com.


So I decided to convert the code into DASM format and create the missing ROM from it. Attached you find the converted source code and the resulting ROM.


BTW: There is a little piece of extra "slowdown/freeze" code in it, which obviously was used for debugging. Also the original code didn't do real bankswitching.

Joust (07-05-1983) (Atari - GCC, Mike Feinstein, Kevin Osborn) (CX2691) (Prototype).zip

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Thanks for sharing this!

I'd like to know more about the dev system used at the time. The fact that they didn't need bankswitching suggests they were using a full 6502 cpu (probably coupled with a ram board where they could upload the code from the dev system).

Source of some of the later games on the 2600 Connection website ("Desert Falcon" and "Dark Chambers") were clearly programmed using the "2600/7800 devkit", composed by a 7800 console + a ramcart connected to an Atari ST. You can see that in those cases the very first operation is to store a value in the 7800 control register to lock the console in 2600 mode. The devkit had 24kB of non-bankswitched ram accessible in 6 4k chunks and the resulting code should run as-is in a 7800 with Eckard Stolberg DevOS and a 48K linear ram cart.

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For Crack'ed they used the same devkit (more info here).


However in Joust, there is no console lock code. And the 7800 wasn't available in 1983 anyway. But for sure they used a full 6502 CPU.


BTW: Most of the larger ZIP files show an error for me. Does anyone know how to fix these?

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E.g. all (?) files which start with wickstead... and VCS_Mr_Do...


I choose several at random of the wickstead docs as well as a couple of the Mr DO ones and had one corrupted download but a retry fixed it. There are PDF's inside the zip files.



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