How to use 555,2x 7490,2x 7447 to count 0 - 60?

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chrisalviola
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I can perform counting 0-99 but how do you stop it in 59 then 00 then back to 01?
heres a sample
 
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heres a sample
 
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You'd have to build yourself a different state machine that could do that. Or, being a CS type, you'd write a dozen lines of code for a microcontroller, providing BCD output to your 7-segment display drivers.

On the assumption that you're looking for some kind of time-keeping device, you can also use an RTC (real time clock). Some even come integrated with crystals (or if not, you can find yourself a 32.768 kHz--2^15 Hz crystal). Heck, I've seen one which was basically an alarm clock on a chip (think it came from Maxim).