Karnaugh maps show race conditions as adjacent minterms that are not covered in the same implicand. Take the following example:
We have race conditions when moving from the blue implicand to the green one, and the blue implicand to the red one (wrapping around the top).
My question is this: would this still apply if the adjacent '1' is a don't care, i.e. an 'X'? In this case, let's change the 1 in minterm AB'CD' (bottom right) to an 'X'. Would this still pose a potential race condition with minterm ABCD'?
Best Answer
Yes it would.
If you experience the transition A'B'CD' → AB'CD' → ABCD', the output should show 0 → X → 1, which is either 0 → 0 → 1 or 0 → 1 → 1. In both cases, you should see a single 0 → 1 transition in the output.
But with your example, you might see 0 → 1 → 0 → 1 in the output: you have a race condition.