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How do I preset a 4029 counter? Answered

Hi all. I am having trouble finding how to preset the minimum output of a 4029. Meaning that I want it to start at an output of 5 (0101) and count up to 15 (1111) and then have it start counting at 5 again. My project is an ASCII counter to check that the ASCII displays with 7 bit binary inputs that I have are functioning correctly and I want to use the 4029 as my input. The problem that I am having is possably misinterpreting the data sheets but is seems that in order to preset the input, the preset pin has to be HI but to run, it has to be LO. Does this mean that I have to set the prest HI, input my preset value of 5, and then bring it LO again to run?  

Any help would be appreciated. Thank you much in advance. 


DON'T let the preset line float either. Make sure its always pulled down by an external resistor, if its not connected to a logic pin.

I tried this but while it starts at 5 and goes to 15, it goes back to 0 for the next cycle. I am looking to start every cycle with 5. Including if it gets unplugged or runs out of power. I am looking for a way to "perminently" start at 5.

Thank you.

I tried that but it just jams. Could that be my wiring? Or more likely a faulty chip?

That is correct. You bring PRESET high, load the desired initial value on the JAM inputs (Q1 to Q4). Then you take PRESET low, and the counter runs. So for your cycle, you will need circuitry to handle that, possibly triggered by the CARRY-OUT pin (which tells when the counter has reached 15).

I am planning to have one 4029 handle the 4 least significant bits and carry out into the one that is preset. Once I load the 0101 that I want onto that one, is there more circuitry needed? I am jus. Getting back into the electronics after quite a while and have forgotten many of these things.

Thank you.