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Timbucus · 24th May 2020, 4:34 pm

Well - I think that is game over. I started to suspect a fault on the 74LS00 due to the lack of a pulse on NRDS/NWDS at any point - looking at the circuit that would never affect the address selection logic if the output would always be high as there is usually a Read or a Write going on. Swapped over the IC11 and IC2 and now the whole board is dead - even when I put them back. I think I may have a fault that is eating 74LS00 - my last two (previously tested) fresh from the pack do not restore operation... maybe I have fried something else...

24th May 2020, 4:34 pm	#245
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,364	Re: Recreating the Bywood Scrumpi Well - I think that is game over. I started to suspect a fault on the 74LS00 due to the lack of a pulse on NRDS/NWDS at any point - looking at the circuit that would never affect the address selection logic if the output would always be high as there is usually a Read or a Write going on. Swapped over the IC11 and IC2 and now the whole board is dead - even when I put them back. I think I may have a fault that is eating 74LS00 - my last two (previously tested) fresh from the pack do not restore operation... maybe I have fried something else...