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Event Counter Revisited...

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I still need some help getting a 00-99 event counter working. This is what I'm trying to do:
I have two multi-color LED bar-graph displays, one of them will indicate 0-9, and the other will indicate 10, 20, 30, etc. This way, only two LEDs will be lit up for any given count. For example, if the fourth LED in the ONES column is lit, and the seventh LED in the TENS column is lit, then the count reads 74. 'Nuff sed.
The problem is: I can't get the @#$%&* thing to work! HELP!! I tried to "cascade" two 4017's, but this is a "carry-out", not a cascade. So, all the data-sheets I've looked at don't show how to carry-out. This can't be that difficult, can it?
As always, your help is very appreciated.


Active Member
Event counter

Why don't you connect the 0 thru 9 outputs of the first 4017 to the 0-9 bargraph leds. Connect the output(pin 12) of the first 4017 to the input of the second 4017 (pin 14). Connect the 0 thru 9 outputs of the second counter to the 10,20 30 bargraph. Use current limiting resistors between the 4017 and the bargraph displays.
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