The Sinclair QL Forum

thx Pr0f, that was my next plan, wiring the shr OE to the ROMOE (inverted) to ensure not driving the bus when i shouldnt (i wanna definitely not damage something). and i need to be more selective (in hardware) so this only happens between c000 and ffff (gal or and, *mabye* the pic's clc because that...

thx Pr0f, i guess i'll try if i could statically set something on the SHR and just drive the databus as long as ROMOE is high to see if it would work if i would not have to shift-out, access the mcu ram and so on. if you say 250ns would be the worst case, and 120s best, i could imagine the PIC cycle...

thx @peter,

puh, 30ns is quite tight.

Hi all, i'm currently trying my first steps with hardware on QL (basically tinkering...) and decided to go for the rom expansion port (not the expansion port on the left). What i basically tried is to use a PIC (PIC18F27K42 @ 64mhz) and wired up A0-A15, ROMOEH and D0-D7, then in the PIC simply check...

Servus from Linz, Austria !

finally, i'm having a QL again !
after like 35 years, and straightaway found my way to this forum with tons of interesting stuff. love it !