At 07:41 am 27 03 2004, you wrote:
>Thanks everyone for the input. It turned out to be a flakey 74153 on the
>memory address bus.
>
>I socketed all 4 of them and things got much worse! I swapped them with
>some from another board and problem solved! It turns out when I socketed
>them I had not tracked which sockets they came from so the bad one was
>moved and caused worse problems in the new location.
>
>I do have a question. I accidentally purchased some 74LS153s and tried
>them and they do not work or are flakey. I know LS TTL chips are slower
>than normal TTL but many times they will work. Is this part speed
>sensitive in this application on the Williams board or is it more likely
>these NOS chips are marginal/bad?
I've used 74HCT153 in the past and they seem to work just as well as
74153. I've never got a 74LS153 to work though ....
Dave Langley
www.robotron-2084.co.uk
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Received on Sun Mar 28 15:31:10 2004
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