Central Point Option Board (earlier non-ASIC version) chips - test-drb@ccmp.vtda.org

1 Dec 2001

ard(a)p850ug1.demon.co.uk (Tony Duell) wrote:
...
  U23 is still a TTL type (a 3-state buffer, not a
counter, now), so data 
 on it is trivial to find. 
Yes, it was the difference in number that suggested a difference in
function and that is why I thought I should bring attention to it.
Not being a hardware guy, I don't have that (number, function) map
cached in my brain.

...
  I don't recognise U3, though. I guess it was made
by UMC. How many pins 
 does it have? 
Eight.  mark_k (who started this thread) told me it is a data separator.

-Frank McConnell