Talk:Bootleg MVS boards

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These are the only clones I've seen, but if any more exist I doubt they will entirely use 74 series for the ZMC2/CT0 logic, at ~16 chips (some uncommon) it would be too expensive and difficult to initially design.

It looks like the "Goldstar" version has the logic in the 4x 22V10, 1x 16V8, 4x '153 and maybe the neighboring '32. It's not very efficient because they aren't using the 22V10 to its potential, they could have eliminated the '153 and also eliminated the 16V8 with minimal 74 series.

The "Gobit" must have it in the "ECW" chip which appears to be a mask clone of the CT0. --Kyuusaku 19:10, 26 June 2012 (CEST)

Curious to see your ZMC2 logic, even though I know releasing it can be an issue as it would be the key to make AES boards. My (tested) schematic has: 2 inverters, one AND, 4*8 bit latches, 3 XORs, a 74163 counter clocked by 12M, 4 74153 4-to-1 data selectors, 2 74157 2-to-1 selectors to handle EVEN and 2 4-input OR gates for DOTA/DOTB. I know there's something made a bit too complicated with the polarity of the clocking edge but... I works about right. Tried it on a EPM420 CPLD, works on the LSPC/B1 AES but glitches on PRO-C0/B0 AESes.

Wonder where's the YM2610 on that "Gobit" board then, was there a SOIC/TQFP version of it made maybe slapped on the back side ? --Furrtek 01:14, 28 June 2012 (CEST)

Yeah you're right, I'm not sure about the YM2610, it could be in the PLCC package and the CT0 could be integrated into the C0, though it would be difficult to find so many free inputs for a CT0. I also don't see the DAC chip. It seems unlikely they'd be able to integrate the YM2610 as easily however.

I'll share the logic soon, I haven't done anything with it in 2 years so it's time.--Kyuusaku 02:59, 28 June 2012 (CEST)