It's an interesting board. Essentially it has both a hard-sectored controller, and a soft-sectored LSI-chip controller, and its own Z80 locally. But what you call "PROMs" also include programmed logic chips, essential to basic operation. You'll have to verify programmed those chips, almost certainly against another working board with working chips. Otherwise it's an exercise in finding someone who can program a brand-variety of PROM and programmed-logic chips by handing them good originals AND sourcing blank chips too. Don't toss ANY chips, that would be my first advice. Good luck. - regards
PS regarding power-supply problems. I read your previous thread, where you describe repeated shorting of the -18V S-100 line. I hope you've resolved that situtation and carefully looked for, and found, and resolved, any other damage to any other board in your NOrthstar system. That can damage any and all boards. It's hard to proceed with confidence when there's uncertainty about the rest of one's system. I'm not being bleak to rub-it-in; I'm saying that unresolved problems will keep tripping up work on other things, like this Morrow board. If for instance, the Morrow doesn't work because some address line from the Z80 CPU board was damaged, you'll go nuts finding that based on DMA floppy controller diagnostics. Good luck on this matter also. - regards
