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How Can I add Counter To This Circuit On Multisim? HELP!

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New Member
Hey Guys I already Have This Project Simulated. How Can I Add A Counter Describe Below:

1. Yellow light Should Be 10 Seconds.
2. Green Light Should Be 30 seconds on the "Solo"
3. Green Light Should Be 45 seconds on secondary avenue.
4. Green light Should be 1 minute on principal avenue.
5. When the Yellow light finish their period, all the lights turn to red for 2 seconds.

Attached the multisim file!

I already try a counter and I failed... I am using a 74LS190N

Here is the equations:

(Principal Green)(PV): A' * C' * D'
(All Yellow)Ay): B * C' * D' + B * C * D + A * C'* D' + A' * B' * C' * D
(Seconday Green)(SG): B * C * D'
(All Red)(TR): B * C' * D + A * C' * D' + A * C * D + A' * B' * C * D'
(Only Way Green) (SoloV): A * C' * D + A' * B' * C * D

Attached the simulation...

Help and example would be veeeery appreciated.



Well-Known Member
I feel you may need to re-do the equations, (if you are using truth table from other post), brackets should be included because (A*B)+C is different from A*(B+C), also this is a light for a cross- road section correct, ie the roads form a + shape? If so then PV(or step 1) = needs to include the green condition for one way PLUS the red condition for the other way. (cant tell if you included it in PV or not)

in the PV equation you say PV is true no matter what condition of B input which is not the case in truth table , *B' needs to be included


Well-Known Member
also I wonder what components are you allowed to use , just logic chips and flip flops? what about timer circuit? are you allowed to use bcd chips and counter chips?

* sorry i cant read multisim
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