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I have never used any Atmel PLD so I don't know.
The Atmel ATF750C also comes in a DIP24 packages (just like a GAL22V10), but it claims to be more complex. I don't understand much to
it's datasheet, tough (now I think I finally understand how PALs works and that is disapointingly simple).
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These do not come in DIP packages
Well, I really want it to be in a DIP package so that it can be easily programmed by an external device (I'm not making it in-circuit programmable).
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Please look at a internal diagram of the 22V10, the flipflop can either be output as the last stage or fed back to the array. If you desire to preform functions on the flip flop's output, you must feed it back into the array and output the combinatorial result on another pin which reduces the outputs by half.
Okay, I think I understand that pretty much. The chip was done so that you could tie it's inputs and outputs together externally to make one pin have more complex sequencial logic than just one latch, right ?
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There is more difficulty however when cascading MUXes (for mirroring) because each I/O has only one SOP term, this will make you again feed your output back to the array.
I think the a way to do it is to manually simplify the thing examintating all possiblities (with Karnaugh maps) and then enter the result logic in your PLD. There is only 4 mirroring configuration possible, that makes a 6 input karnaugh map (heavy !) but it will siplify a lot.
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For MMC1 you need a clock for the shift register and write counter, and 4 separate clocks for the registers, for those parts alone that's 6 PLD
I think a single 74139 can handle all those clocks. I think something using 74164 (shift register)+74139 (clock & register adress decoder) + 74161 (write counter)+4x74378 (registers in question : wasting so much chip for these is really a lame) + Atmel PLD should do, that makes 8 chips (blah... I'd like to see it reducted to 3 chips or something...)