Yes the counting is syncronous. That was never the issue. It is the LOAD(PL*, pin 11) and the RESET(MR, pin 14) which are asyncronous. It is difficult to make a counter with an asyncronous load behave properly in the OPs application. It is far superior to use a counter with a syncronous load. Just take my word for it and dispense with all the other claptrap.ericgibbs said:hi hjames,
The LS193 is a synchronous counter, not a async/ripple thru counter.
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