Re: Cascading two 74LS90's doesn't work (needs deglitching)

On Apr 26, 5:00 am, "petrus bitbyter"
<pieterkraltlaatdit...@xxxxxxxxxxxxxxxxx> wrote:

You're using some wrong counters. To make seconds from 60Hz, you'd better
use half a LS92 counter, followed by an LS90. You can use the circuit to
make minutes from seconds. Both types are ripple counters, so the outputs do
not change at the same time but they have no glitches. Glitches only occur
when you combine outputs with glue logic like gates. Maybe you can't trust
Gates anyway :)

petrus bitbyter

Thanks for your suggestions Petrus, see my reply above for where
things are now at.
regards
Peter
.

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