How Do You Identify XOR in Karnaugh Maps?

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SUMMARY

The discussion focuses on identifying XOR in Karnaugh Maps using Reed-Muller logic. The minimum Boolean expression derived from the map is Z = ¬a ⊕ b ⊕ c ⊕ d. Participants detail the process of circling groups of ones and zeros while ensuring the parity conditions are met. The final expression is confirmed through various combinations and simplifications, emphasizing the importance of understanding XOR and XNOR relationships in Boolean algebra.

PREREQUISITES
  • Understanding of Karnaugh Maps and their application in Boolean simplification.
  • Familiarity with Reed-Muller logic and its principles.
  • Knowledge of Boolean algebra, specifically XOR and XNOR operations.
  • Basic skills in logical expression manipulation and simplification techniques.
NEXT STEPS
  • Study the properties and applications of Reed-Muller logic in digital design.
  • Learn advanced techniques for simplifying Boolean expressions using Karnaugh Maps.
  • Explore the differences between XOR and XNOR operations in digital circuits.
  • Practice solving complex Boolean expressions with multiple variables using K-maps.
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Students in computer science, electrical engineering, and anyone involved in digital logic design who seeks to deepen their understanding of Boolean algebra and Karnaugh Maps.

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Homework Statement



Using XK-map techniques, obtain the minimum Boolean expression for the following map:

Screen Shot 2015-04-19 at 1.58.29 PM.png


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The Attempt at a Solution



So I've been doing some reading and I found this has to do with Reed Muller logic. This was unfortunately not covered in the course I'm taking, so I'm a tad bit confused.

How exactly am I supposed to circle this map? I know I have to circle groups of zeroes and ones such that the parity of the ones is odd and the parity of the zeroes is even.

For reference, the answer is listed as:

$$Z = \bar a \bigoplus b \bigoplus c \bigoplus d$$

I have experimented with a few circling combinations, but cannot find one that gives the answer above.
 
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You could "circle" the four "0" for not A i guess. They all have odd parity for B,C,D. Similar for A.
That does not give nice square blocks - it cannot, you are looking for XOR.
 
After staring at this for a few more minutes, I came up with this:

Screen Shot 2015-04-19 at 1.58.29 PM.png


So the black box would be ##\bar a##. The red box would be ##b##. The blue box would be ##c##. The green box would be ##d##.

So ##z = \bar a \oplus b \oplus c \oplus d##.
 
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I am in high school and my Computer Science teacher teach us this and I figure it out by kinda like a Math way.
First I list out all the 1s.
A'B'C'D'+A'B'CD+A'BC'D+A'BCD'+ABC'D'+ABCD+AB'C'D+AB'CD'
=(A'B'C'D'+A'BCD'+ABC'D'+AB'CD')+(A'B'CD+A'BC'D+ABCD+AB'C'D)
=D'(A'B'C'+A'BC+ABC'+AB'C)+D(A'B'C+A'BC'+ABC+AB'C')
=D'(C'[A'B'+AB]+C[A'B+AB'])+D(C[A'B'+AB]+C'[A'B+AB'])
RECALL THAT
A'B + AB' = A XOR B
A'B' + AB= A XNOR B

=D'(C'[A XNOR B]+C[A XOR B]) + D(C[A XNOR B]+C'[A XOR B])
WHILE XNOR = (XOR)'
=D'(C'[A XOR B]'+C[A XOR B]) + D(C[A XOR B]'+C'[A XOR B])
=D'([A XOR B] XNOR C)+ D([A XOR B] XOR C)
=D'(A XOR B XOR C)' + D(A XOR B XOR C)
=A XOR B XOR C XNOR D
=A ⊕ B ⊕ C ⊕ D'
OR IF U PULL OUT 'A' AT FIRST IT WILL BE THE SAME
 

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