Tech : Atari System 1 General Questions (PCB type, LETA, Mix n' Match) ?

Never ever seen a IJ TTL cart, only a MM
Was a bit surprised myself. Documented the rom versions and locations for posterity. I really need to post up the info before my little notebook gets lost in the upcoming move.
 
Here you go then: ArcadeRomPatcherV12.rar ;)

This issue with the later LSI carts such as RB Rev4 is that you also need to mod the BSProm due to the eprom size changes. There is also another type of RB LSI cart that has some patch wires with an extra TTL buffer that can be a pain to convert.
I spent a lot of time working on the Atari System 1 stuff and in the end came up with my multi cart https://forums.arcade-museum.com/threads/atari-system-1-multi-cartridge.479793/

The Slapstic removal for System 1 was actually quite easy in the end. The first game I did was Marble Madness which actually turned out to be the hardest. Of course it wouldn't have happened without Mame debugger which was invaliable.
I did look at doing System 2 de-slapping but they are not used in the same way as the signals out from the Slapstic are used in hardware not just to select a diffrent rom bank as in System 1.
 
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I'm reviving this thread, because the collector I'm working with put the MM eproms on a working RB cart (older Rev 3 board),
and is getting a Bank Switch error.

I suspect this has to be some kind of eprom sizing issue.
Possibly with the jumper wires added for the RB eproms ( which would not be needed for MM ) ?

Anyone ?
Thanks
 

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Bank error is almost always the 2 EPROMs next to the slapstic or the Slapstic itself, Slapstic for mm must be a 103 or 110. the added jumper wires are on graphics Roms which have nothing to do with the bank switch error
 
Bank error is almost always the 2 EPROMs next to the slapstic or the Slapstic itself, Slapstic for mm must be a 103 or 110. the added jumper wires are on graphics Roms which have nothing to do with the bank switch error

Thanks, we'll try that, and get back to you.

Steph
 
Sorry, just to be clear , when you say "2 eproms next to the slapstick" ,
do you mean the two smaller proms at location A5 and A7 ?

... or the actual eproms near the slapstick which is A15/16 ?
 
Sorry, just to be clear , when you say "2 eproms next to the slapstick" ,
do you mean the two smaller proms at location A5 and A7 ?

... or the actual eproms near the slapstick which is A15/16 ?
I'm talking about EPROMs at 17a and 17c , don't worry about anything on the left hand side of the cartridge until you have a running cartridge
 

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Also, check the sockets for those 2 roms as well. Can't tell you how many carts I have repaired where the problem was crappy sockets.
 
Maybe dirty sockets but road blasters worked before I tried the marble madness conversion
 
There are also LSI and TTL versions of Indiana Jones. I have one of the TTL carts. 😁
I know this is an old thread, but I believe I have both versions of the Indy cart.

I have the TTL mainboard, but both carts work. They have different ROM numbers though.

If I wanted to convert one of the carts to Marble Madness, would it be better to convert the TTL or LSI cart, and has anyone done this before?

It would be nice to document the different main boards, and their compatibility with various carts, and what's needed to convert between them successfully. Some of that has already been discussed here.

That said, if anyone has a working MM cart, I have a working Indy cart if anyone wants to trade.

Thanks!
 
I know this is an old thread, but I believe I have both versions of the Indy cart.

I have the TTL mainboard, but both carts work. They have different ROM numbers though.

If I wanted to convert one of the carts to Marble Madness, would it be better to convert the TTL or LSI cart, and has anyone done this before?

It would be nice to document the different main boards, and their compatibility with various carts, and what's needed to convert between them successfully. Some of that has already been discussed here.

That said, if anyone has a working MM cart, I have a working Indy cart if anyone wants to trade.

Thanks!
It's just burning new roms and adding the correct slapstic. You're correct that the rom numbers are different, but that's a function of the size roms they used between the two board types and the revision of the software loaded for that board.
 
It's just burning new roms and adding the correct slapstic. You're correct that the rom numbers are different, but that's a function of the size roms they used between the two board types and the revision of the software loaded for that board.

I wish it were that simple...

As someone who's often tried to help people make Sys-1 conversations with eprom swap,
it's not as easy as it sounds.

There are 4 different Sys-1 cart versions ,and MarbleMadness alone has 5 different rom sets.
(with different rom sizes and locations , with either 27 , 23 or 18 roms).
not to mention the TTL vs LSI mother board options.

Even if you use the cracked Slapstick versions , Getting the right combination is not obvious.

Depending on the cart version, there are jumpers to set for eprom size
and specific proms used for address decoding.

If someone has a definitive way to convert from one game to another,
I would LOVE to see it. ;-)

Thanks,
Steph
 
I've done it. But, you're right in that you have to have the correct rom layout and sizes. There's also some variation with later revision roms, but generally 27128's got upgraded with 27128's, etc. I've documented a few MM revisions, but I'm sure there are more than I've got.
 
Here is a link to my google drive with a copy of my lastest Patcher version:
https://drive.google.com/file/d/1yt0aONAzfLiEYH0RrzNc0ZzvibeOrZ_E/view?usp=sharing
As for getting rom sets to work on different cart versions it isn't that difficult to do. Just use the Mame source file for rom locations and the right schematic pdf for your cart version. The only issue occurs with a couple of games and the later cart versions because then sometimes you need to mod the prom files.
If I ever find the time I could document a lot of the work but time is one thing I never seem to have enough of ;)
 
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