How does 32 in One work?

[davidbrit2]

This has been bugging me for such a long time. How does the 32 in One cartridge "remember" which game to start with next? It seems like any RAM in the cartridge would be cleared when power cycling the Atari, and I doubt they would have put in some EPROM or battery back up. I don't want to open mine up so as not to wreck the label. Has anyone seen how it handles game selection?

[liquid_sky]

david, here is a excert from kevin hortons technical file on the 32 in 1 cart... hope it helps

 

t's very simple, just a 27512-style ROM (64K), a binary

counter (4024), and a hex inverter (74C14). Every power on/off/on cycle

increments the counter once, which brings up the next game. Sounds good

in theory, but it doesn't work too well in practice! :-) Usually it'll

skip counts, so that you have to keep turning it on/off/on/off to get to

the game you want to play. I manually incremented the counter and read

the games one at a time. This allowed me to tell the exact order the

games are really in, and to fairly easily get each one. Each game is

2K, and since there are 32, the total amount of memory is 64K.

[davidbrit2]

That sounds pretty good, except for one thing: how does the counter keep data without any power from the Atari?

 

And by the way, 32 in One is a pain on the 7800. Especially a really heavily used one, with a worn power switch.

[liquid_sky]

i can imagine... im not 100% (heck not even 1%) sure on how it keeps data without power, but if i find out ill make sure to post it here

[davidbrit2]

I know how that feels. As much as I would like to be, I'm not much of an electronics guy. Otherwise I would probably have figured it out by now.