I got a digital design problem. My final implementation of the circuit program didn't achieve the required criteria, so I brought my problem and my works here to be suggested by you if I mis-manipulated any details.
Logic System: Binary--1,0.
Issue after Simulation and Test on Circuit Board: LED lighted up at the begining without any switches were turned ON. (Would it make sense?)
Problem Statement:
Use 4 switches A, B, C, D to control a LED. LED is ON if the following conditions are satisfied,
D and B turn ON,
or A turns OFF while C turns ON,
or A and B turn ON and the rest turn OFF,
or C and D turn OFF,
or all switches turn ON.
End of Problem Statement.
Notations and Circuit Combinations we use:
AND gate: · (dot)
OR gate: +
"Not/Invert something": ~
SOP: Sum of Products
POS: Product of Sums
SOP and POS are equivilant to each other.
My works:
True Table based on the 5 criteria
ON:1, OFF:0.
Collection of LED results is {1011111110001101}.
I can handle operating the software part, but I really want to check with you guys if I use POS method and based on the 5 criteria given in the problem, whether or not my true table is correct.
Please help me to point out my blind spots. Thanks