Assignment:
Consider the attached circuit. Assume that the three states are initially at the 0 logic level. Which of the given tables is true for the function performed by this circuit? The leftmost column represents the clock pulses. Initially there is no pulse (1st row). As the first clock pulse arrives the resulting change of state is shown on the second row and so on.
A B C D
C Q1 Q2 Q3 C Q1 Q2 Q3 C Q1 Q2 Q3 C Q1 Q2 Q3
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1 0 0 1 1 0 1 0 1 1 0 0 1 1 0 0
2 1 0 0 2 0 0 1 2 0 1 0 2 0 0 1
3 0 1 0 3 1 0 0 3 0 0 1 3 0 1 0
4 0 0 1 4 0 1 0 4 1 0 0 4 1 0 0
5 1 0 0 5 0 0 1 5 0 1 0 5 0 0 1
6 0 1 0 6 1 0 0 6 0 0 1 6 0 1 0
7 0 0 1 7 0 1 0 7 1 0 0 7 1 0 0