Atari 7800 Alternative BIOS/Firmware

[+bhall408]

Has anyone done/does there exist a non-Atari replacement/alternative BIOS for the 7800?

 

If not, considering doing that...

 

 

[Trebor]

3 hours ago, bhall408 said:

Has anyone done/does there exist a non-Atari replacement/alternative BIOS for the 7800?

 

If not, considering doing that...

 

 

Yes, there are several along with the system originals:

 

7800MULTIBIOS.zip

[+bhall408]

That is pretty cool -- I had been aware of the PAL and NTSC variants.

 

In particular, I'm looking for non-Atari ones, that would be OK to use commercially.

 

As the BIOS is pretty small, if one doesn't exist, I'll start working on one.

 

[RevEng]

The bios doesn't do anything important for the game, other than switching between 7800 and 2600 mode. If we're talking about emulation for games here, you can just start the emulator with the cart image mapped in.

[+bhall408]

1 minute ago, RevEng said:

The bios doesn't do anything important for the game, other than switching between 7800 and 2600 mode. If we're talking about emulation for games here, you can just start the emulator with the cart image mapped in.

I had assumed it was at least setting up/initializing chips, etc.

 

If that technique works, then by all means, that is the best option for us (as an emulator).

 

We'll give it a try!

 

We're not quite ready yet (we're finalizing for a public beta this month with the existing cores), but we have started on it. It is a mix of the BSD parts of 7800 from MAME, some code of our own, a blended TIA and other things that were GPL. We realize the MAME core for 7800 isn't considered the most up to date, but we'll fix it as needed as we go.

 

[+-^CrossBow^-]

18 hours ago, Trebor said:

Yes, there are several along with the system originals:

 

7800MULTIBIOS.zip 114.95 kB · 6 downloads

Eckard's DevOS isn't included in that zip? I realize it isn't for general gaming use but it literally has the option to choose which mode you want to change to on it and I figured that could be handy for some?

 

[TailChao]

17 hours ago, bhall408 said:

I had assumed it was at least setting up/initializing chips, etc.

 

If that technique works, then by all means, that is the best option for us (as an emulator).

It does do some light initialization and hardware tests, therefore leaving everything in a slightly different state than a cold boot. But you can also just duplicate this condition instead of writing your own BIOS / Boot ROM.

[Trebor]

1 hour ago, -^CrossBow^- said:

Eckard's DevOS isn't included in that zip? I realize it isn't for general gaming use but it literally has the option to choose which mode you want to change to on it and I figured that could be handy for some?

Good point.  Having both the first and second release packages, I should have extracted the BIOS files from each and included them.  Come to think of it, I should add a BIOS section to the PROPack and have all BIOS files there as well. 

 

Anyhow, here are the two released Eckhard packages from 1999 and 2000 respectively.  Each contains the respective BIOS and support files.  Additionally, attached below is the "Development Cartridges For The Atari 7800 Development System" PDF Revision 14, document from 2003, for posterity as well:

 

Atari 7800 Development System (First Release) (Eckhard Stolberg) (1999).zip

Atari 7800 Development System (Second Release) (Eckhard Stolberg) (2000).zip

Development Cartridges For The Atari 7800 Development System (Rev 14) (2003).pdf

 

As with all BIOS files and/or dev kits provided, you're on your own folks.  No warranty or support implied.  Use all of this at your own risk.