# Flip Flop problem

Discussion in 'Homework Help' started by Cheezy, Feb 1, 2013.

1. ### Cheezy Thread Starter New Member

Jan 22, 2013
4
0
The whole sequence takes 16 seconds.

[Step 1] From 0 - 4 seconds , G1 on , R1 off , G2 off , R2 on.

[Step 2] From 5 - 7 seconds , G1 off , R1 on , G2 off , R2 on.

[Step 3] From 8 - 12 seconds, G1 off , R1 on , G2 on , R2 off.

[Step 4] From 13-15 seconds, G1 off, R1 on, G2 off , R2 on.

This is a Traffic Roadwork question. This is my circuit and I cant understand which part of it went wrong , I made a K-map for G1 and G2 when they are on and implemented it onto my circuit then i simply inverted them to R1 and R2 respectively since when green is on, red must be off for a traffic. The flip flops are basically numbers from 0 to 15 so I know at which seconds they are currently at. Help would be appreciated if someone can point out to me where I made the mistakes.

2. ### WBahn Moderator

Mar 31, 2012
23,743
7,302
It would help if you described what your circuit is doing or not doing that indicates that it is wrong.

Show us your work (and the circuit certainly counts towards that). But show us your K-maps and also the equations you got from them. That way we can see at what point you made your mistake and guide you toward finding it yourself.

Also, indicate on your diagram which signal is the msb and which signal is the lsb of your counter. Then make sure that your logic doesn't, say, have them reversed.