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I want to see if my boolean algebra is correct.

Harald Kapp

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It's lab experiment #7 street lamp circuit.
#7 is the traffic signal, is that's what you mean?
Your equations should be stated in the form:
R1 = f(Qa, Qb, Qc, Qd)
Y1 = f(Qa, Qb, Qc, Qd)
G1 = f(Qa, Qb, Qc, Qd)
etc.
 

Circuit_analogy

Jul 13, 2015
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Yes the traffic signal, Though I remember it looking like this(vaguely).

QA=0

QB= A'B'C + A'BC' +AB'C'- I forgot this part
G1 Y1 R2

QC= 0

QD= AB'C'+A'B'C+A'BC'
R1 G2 Y2
 

Laplace

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The usual method to get logic from a truth table is to generate a Karnaugh map for each column (output) in the table, minimize the K-map, and implement the result in gate logic. Three examples are attached for the R1, Y1, & G1 outputs. (But did not ask TINA to provide the gate implementation.)
 

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  • EP64-R1.png
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  • EP64-G1.png
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  • EP64-Y1.png
    EP64-Y1.png
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Harald Kapp

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Qa, Qb, Qc, QD are the outputs of the 74193 counter and are the inputs to the logic that decodes the lights' status from the count value (table on page 22).
R1, G1, Y1 etc. are the outputs of the logic that represent the state of the different traffic lights.

Therefore you need Qa etc. as inputs to your logic equations, R1 etc as outputs. Once you have these equations (check Laplace's post), they can be checked for correctness.
 
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