Build a state machine diagram. Figure out the patterns by which one state goes to the next. The inputs are the current state and any inputs, and the output is the next state. Then add the JK excitation that brings you to the next state. Make sure, at this point, that you have no duplicate states (i.e. states that with the same input that end up at all the same outputs) and eliminate them if you do. Once you have this, then start building Karnough maps for the outputs and JK excitations until you feel like you are ready to implement the resulting logic.
Ignore what they are calling it and draw a truth table for what they describe. There appears three inputs: "the current state" which you can arbitrarily call Q(n), N, and M. There is one output which we can arbitrarily call Q(n+1). The names are not totally arbitrary, because Q(n+1) is by definition a one-time-step delayed version of Q(n) (i.e. Q(n) is the previous output).
Inputs Outputs
Q(n) M N Q(n+1)
0 0 0 ?
0 0 1 ?
0 1 0 ?
0 1 1 ?
1 0 0 ?
1 0 1 ?
1 1 0 ?
1 1 1 ?
You should be able to fill in the question marks from the narrative description trivially. This is a truth table.
I believe an excitation table is just a rephrasing of the truth table where the valid entries are include 0, 1, and Q(n) and it's complement /Q(n) (so there are only two "real" inputs). And removing "redundant" rows (i.e. if a variable is a don't-care under some conditions, then express that collapsed row with an "x" for that variable).
Inputs Outputs
M N Q(n+1)
0 0 Q(n), /Q(n), 0, or 1?
0 1 Q(n), /Q(n), 0, or 1?
1 0 Q(n), /Q(n), 0, or 1?
1 1 Q(n), /Q(n), 0, or 1?
Can you reduce this further once you put answers in to the question marks?
Best Answer
Just put an X to mark don't care, meaning the next stat can be 1 or 0.