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Jonathan Luthje
¿ªÔÆÌåÓýNick,
??? There are probably a thousand or more different ways of making either a
1Hz oscillator or a debounce switch, with a thousand or so different IC's, one
of the simplest methods (to kill two birds with one stone so to speak) would be
to use the LM/NE555 timer IC. And perhaps (although I'm not so sure it would be
accurate enough to make say - a clock) it would even be able to function as a
timebase for your clock. Configure it in monostable (one-shot) mode for a switch
debouncer or astable (multivibrator) mode for a timebase.
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Come to think of it, I may have been initially
wrong with my "how you are going to make a clock with those I don't know"
statement. Come to think of it, it probably wouldn't be all that difficult. If
you do it in the way you describe, it is entirely possible, although perhaps not
all that accurate, using the public power supply (which isn't known to be
absolutely spot on, but I guess you can always add another timebase later if
need be.
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Yes, you just need to feed low voltage un-rectified
AC (i.e. 60Hz) to the clock pin of the counters and feed the corresponding
outputs into perhaps some AND gates (if the binary value needed uses more than
one bit) which feed into the clock pin of some more counters, and feed the
output of the digit-counters into some binary-to-BCD converters and then into
some LED 7-seg display units. It can be done ... perhaps with a lot of chips,
but it can be done.
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There is loads of info on 555 timers about the
place, but if you come up?blank ... post another message and I will post up
some suggestions for circuits.
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Let me know how you get on,
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JOn ?
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