Major Havoc - Leta or Pokey or Both?

Huh, he's right. We have a winner.

I can do this in mame. Booting up to test mode yields a pokey error. Resetting while in test mode, or going from game mode to test mode does not yield a pokey error (in mame). And wouldn't you know it? My machine is behaving the same way. No pokey error if I go from game mode to test mode.

Have I been chasing my tail this whole time?

I guess it really is just the Leta.

It's got to do with the difference in execution paths through the code altering the "startup" sequence when it encounters the self test switch being on vs off (to game mode).

I'll send a bill later in the week.
 
Huh, he's right. We have a winner.

I can do this in mame. Booting up to test mode yields a pokey error. Resetting while in test mode, or going from game mode to test mode does not yield a pokey error (in mame). And wouldn't you know it? My machine is behaving the same way. No pokey error if I go from game mode to test mode.

Have I been chasing my tail this whole time?

I guess it really is just the Leta.

are you getting the roller enable signal?
 
This caught my eye in the list of Atari number thread I recently made, I've never heard of a LETA eliminator, I wonder if it was an all logic chip replacement daughter board...

If only this forum had a search function...

 
They exist but are hard to find:

20140208_155523-jpg.169200


 
They exist but are hard to find:

20140208_155523-jpg.169200




Could be made smaller with smd componets, not as small as the the fpga, which is probably still the best route. I wonder if it just wasn't a big seller so it wasn't worth recreating it for the currently available fpga.
 
Could be made smaller with smd componets, not as small as the the fpga, which is probably still the best route. I wonder if it just wasn't a big seller so it wasn't worth recreating it for the currently available fpga.

I'm not doing this work so this is what my old brain is remembering here... but it seems that a lot of the FPGA or whatever tech that's being used was moving away from supporting the TTL level stuff. The parts are becoming obsolete essentially. I know the I Robot ICY project was finding it difficult to find chips that would support the old hardware and also not draw too much current.
 
It does seem like FPGAs go obsolete a often. The bitkit is on its 2nd or 3rd FPGA.


Maybe a small daughter card with smd parts would make sense. That PROM might be the only full size thing that is needed.


Though based on 2600's comment HERE the LETA eliminator doesn't recreate the whole chip.


Edit* good jrok info HERE.


This is what killed the availability of these
 
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