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From: wb8foz@mthvax.cs.miami.edu (David Lesher)
Newsgroups: sci.electronics
Subject: Re: EVENT COUNTER
Keywords: counters,data aquisition
Message-ID: <1990Sep1.133327.12909@mthvax.cs.miami.edu>
Date: 1 Sep 90 13:33:27 GMT
References: <26dd5749-39csci.electronics@vpnet.chi.il.us> <26de96e2-39c.1sci.el <26ded58a-39c.2sci.electronics-1@vpnet.chi.il.us>
Reply-To: wb8foz@mthvax.cs.miami.edu (David Lesher)
Organization: NRK Clinic for habitual NetNews abusers
Lines: 21


[needed debouncing, if I understood correctly]

I built some special IO boards for a DEC Falcon {a micro-PDP-11 beast}
that had to debounce switch inputs. I used a 16 pin dip hex debouncer.
I *think* it was a 14490, or 14409, but it's been a while;-}

In any case, its law was simple: For the output to go up, the input had
to go up and stay up for 5 periods. To then go low again, it had to go
low and stay low, etc. You set the period of the internal clock with a
cap I recall. There was WIDE variation in periods available -- maybe
large us to several seconds.

It worked well for me on several hundred boards with 8 per board. But I
should mention that another designer cursed it roundly, as he never had
any luck with it.
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