Quote:
Originally Posted by SiriusHardware
This is my modified version of the _CE circuit. What have I done wrong? Yes, I could have used a 74x02 but there was already a 74LS27 in place.
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Yes that was what I was going to suggest, using a 74x02, and according to the simulator it should be OK:
Code:
ian@FX503VD:~/Projects/Test$ python2 ~/Bin/lsim mk14ram.sim
.inputs a11 a10 a9
.outputs CE
x: nor a10 a9
y: nor x a11
CE: nor y y
a11 a10 a9 | CE
-----------+----
0 0 0 | 1
0 0 1 | 0
0 1 0 | 0
0 1 1 | 0
1 0 0 | 1
1 0 1 | 1
1 1 0 | 1
1 1 1 | 1
(in the attached image the NWDS and NRDS are swapped (Doh!))