Dear all,
I am building a real time clock using 555time as 1000ms pulse input to bin counter and displaying second, minute and hour by successive counters.
Still now i got an exact 50% dutycycle from 555timer and i need information of how to interface counter and 555timer & 7 segmentdisplay with counter . plzzzzzzzzzzzzzzz help me out.....
REGARDS
KALMESH

 

I am a fan of the 555, but it makes a lousy precision time source. You'd be better off with a 4060 chip using a crystal.

As to the counters, the 555 as a time base is the barest beginning of a clock. Here is a block diagram I drew up for these kind of questions a while back.

If you were using TTL logic the 7490 and 7492 are mod 10 and mod 12 counters respectively.