The idea is easy, but the TTL to do it is not. Since I've already got my CPLD stuff on the bench, let me see if I can help you out there. But, you would prefer, no doubt, something that plugs inside the case, not hang off the exp port. Stuffing it under an IC inside the unit, and then sucking a IO select from somewhere would be ideal. My first thought would be the SID (R/W line, some address lines, data lines, phi, pwr, gnd), but other places might be even better. If you wanted to use the SID space, you have 3 registers there that conflict with nothing else: $d41d,e,f You could do something like: $1d = register $1e = value That would give access to a max of 256 LEDs, or you could do something more esoteric. A CPLD could get you 8-10 registers in that fashion, if that's of interest. jim Message was sent through the cbm-hackers mailing listReceived on 2016-01-22 01:00:11
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