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assemblyboolean-logiccircuitkarnaugh-map

How to generate Karnaugh maps from state transition table?


I have a state transtion table that looks like this:

enter image description here

And the binary equation obtained from this is:

enter image description here

I don't have any example in my text book that solves this table with Karnaugh map. The text book just states that it can be done by inspection and I am confused about the process.

Can someone please help me covert this to Karnaugh map and solve it?


Solution

  • There two tricks, basically-- 1: Convert the given "don't care" Xs to 1s and 0s (see "[1]" below for first given "don't care" X) 2: Note that the outputs are never both 1 (see resultant "don't care" Xs below) Truth Table, Completed:

    S1 S0 A B  S'1 S'0
    0  0  0 0  0   0 [1]
    0  0  0 1  0   0 [1]
    0  0  1 0  0   1
    0  0  1 1  0   1
    0  1  0 0  0   0
    0  1  0 1  1   0
    0  1  1 0  0   0
    0  1  1 1  1   0
    1  0  0 0  0   0
    1  0  0 1  0   0
    1  0  1 0  0   0
    1  0  1 1  0   0
    1  1  0 0  X   X
    1  1  0 1  X   X
    1  1  1 0  X   X
    1  1  1 1  X   X
    

    This results in the following S'1 Karnaugh Map:

    S1S0\AB 00  01  11  10
    
    00      0   0   0   0
    
    10      0   0   0   0
               _______
    11      X | X   X | X 
              |       |    
    01      0 | 1   1 | 0
              ---------
    

    This results in a minimized Sum Of Products of:

    S'1 = SoB 
    

    S'0 is determined similarly.