# I want to see if my boolean algebra is correct.

Discussion in 'General Electronics Discussion' started by Circuit_analogy, Jul 13, 2015.

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Jul 13, 2015
2. ### Harald KappModeratorModerator

11,811
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Nov 17, 2011
#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.

3. ### Circuit_analogy

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Jul 13, 2015
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

4. ### Laplace

1,252
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Apr 4, 2010
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-Y1.png
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5. ### Harald KappModeratorModerator

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Nov 17, 2011
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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