This morning, I wired 65C51 and 65C22 IRQ lines with AND logic and then tested handling interrupts from both in software. I'm a step closer to having the connections for this machine finalized
and moving from breadboards to either wire wrap or PCB, neither of which I've done before.

A quick search suggests it costs less to get multiple smaller PCBs than a single larger one. If I go with PCB, I may put processor, VIAs, CIAs, ROM, RAM, and addressing decoding and glue logic
on one board, the LCD on another board, forthcoming sound generation hardware on a
3rd board, and so on.

If I go with wire wrap instead, increasing prototype board size doesn't affect cost as much.
So I might try to get everything I can on one board.


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@daremo Building wire-wrap boards becomes tedious very quickly. I haven't done it since the early 1980s.

I like the challenge of going straight to PCB. It focuses the mind on checking the design and board layout for correctness.

@neildarlow Any recommendations for short run fabs? seeedstudio has a 100x100mm board for $5 that might be fit for my purposes.

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