I don't like the way it works.
I would use only one "555" oscillator.
Make the two 7490s count as one.
(clock to CKA, QA to CKB, QD to CKA2, QA2 to CKB2,)
Counts from "00" to "99". But you want it to count 00 to 32. 32=0011,0010
Add a gate that detects 32. xx11, 0010. (x=don't care) When 32 then reset the two counters (will happen on the next clock)
I think this will work xx11, xx10 ??? You need to think about this.
> 0011,0000=30, 0011,0001=31, 0011,0010=32, so look for xx11,xx1x or a 3 input AND gate.
I thought the black/red was as simple as odd/even or just QA1. ???
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7447:
The RBI pin will blank when "0".
Without RBI a zero ="00"
With RBI on one IC, zero = " 0" or "0 "
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what CAD program are you using?
The green LED is xx00,0000, = green
OR
You could take the "32" signal and delay it by one count.
>use a D FF. Clock to CKA1, Data from "32" This will cause 32 delayed by one clock to be at time "00"
The random number is a function of when you pull your finger off the switch. If you add the function in post #22 you will get some "random" after the finger is removed. The count will go around several times more after the finger is removed.