Sequential Logic

I am trying to make a traffic light and having a bit of trouble gating the circuit to change states. Is there something I am missing. Please help.

by s3665153
September 09, 2018

Try using a 555 timer and a 4017 counter followed by diode logic to get the four states, 1234 red 5 red amber 6789 green 10 amber,

by mikerogerswsm
September 09, 2018

I am hoping to only make use of D flip flops.

by s3665153
September 09, 2018

Impossible - you will need first to generate a clock!

by mikerogerswsm
September 09, 2018

If you look at a 4017 datasheet you will see a Johnson twisted ring of five D flip flops and some logic gates. You will need some glue logic instead of diodes to detect the 1234, 5, 6789 and 10 states. Also some lamp drivers. End. mike

by mikerogerswsm
September 10, 2018

Thanks will do.

by s3665153
September 11, 2018
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