Answers Database
M1 docs., library guide,X74_168: Fig. 12.12, shown cascading counter is wrong.
Record #3389
Problem Title:
M1 docs., library guide,X74_168: Fig. 12.12, shown cascading counter is
wrong.
Problem Description:
Keywords: carry, logic, cascade, x74_168, 74168
Urgency: Standard
General Description:
Fig. 12-12 in M1 documentation CD shows how to cascade x74_168
with carry lookahead.
The figure is wrong.
ENP of the first stage and ENT of the second
stage should be connected to GND.
The connection shown is to VCC. With this connection, the
counter will not count up/down.
Solution 1:
Change the ENP of the first stage and ENT of the second
stage connection to GND.
End of Record #3389
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