Bog standard Master 128 - odd CMOS behaviour.
Power on with 'R', prompts for <break>, then returns startup banner however typing anything yields crazy repeat/delay sssssssssssseeeeeeeeeeeettttttttttttttiiiiiiiiiiiiinnnnnnnnnnnnnngggggggggggggsssssssssssss.
Deft fingerwork enabled me to enter *ST. and it showed both repeat & delay set to 1. Repeated 'R' power-ons yielded same results.
I created a disk on another Beeb, the !boot of which contained *co. delay/repeat 50 which then allowed me to use the machine.
*ST. showed delay and repeat both at 51. Set it to 40 and *ST. showed 41.
I had a 80186 board installed and that was always enabled. No combination of *extube or *notube would disable it.
So, completely strange behaviour.
Posted on *. and after a bit of back-and-forth I ordered a replacement CMOS chip, socketed the mobo and fitted the chip.
Sane operation resumed.
Power on with 'R', prompts for <break>, then returns startup banner however typing anything yields crazy repeat/delay sssssssssssseeeeeeeeeeeettttttttttttttiiiiiiiiiiiiinnnnnnnnnnnnnngggggggggggggsssssssssssss.
Deft fingerwork enabled me to enter *ST. and it showed both repeat & delay set to 1. Repeated 'R' power-ons yielded same results.
I created a disk on another Beeb, the !boot of which contained *co. delay/repeat 50 which then allowed me to use the machine.
*ST. showed delay and repeat both at 51. Set it to 40 and *ST. showed 41.
I had a 80186 board installed and that was always enabled. No combination of *extube or *notube would disable it.
So, completely strange behaviour.
Posted on *. and after a bit of back-and-forth I ordered a replacement CMOS chip, socketed the mobo and fitted the chip.
Sane operation resumed.
Statistics: Posted by ihardcas — Fri Jun 06, 2025 1:00 am