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.
How about an inexpensive motherboard layout with right angle header pins like the RC2014?
@oranje I'll def. take another look at RC2014 for inspiration. I met and talked to Spencer, its creator, at the hackaday con, btw.
As a complete beginner, I just need to dive in: do a couple hours research on PCB construction and try the PCB tool in kicad.
@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.
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.