U11 Truth Tables

Reverse engineered Apple II hardware

U11 Truth Tables

U11 is a PAL16R6 which has two purely combinatorial outputs and 6 registered outputs which latch new values when the CLK signal is pulsed.

Output IO1 (combinatorial)

I5 I6 I7   IO1
0 0 0   0
0 0 1   0
0 1 0   0
0 1 1   0
1 0 0   1
1 0 1   1
1 1 0   1
1 1 1   0

Output O2 (registered)

O2 O3 O4 I2   O2
0 0 0 0   1
0 0 0 1   0
0 0 1 0   1
0 0 1 1   0
0 1 0 0   1
0 1 0 1   0
0 1 1 0   1
0 1 1 1   0
1 0 0 0   0
1 0 0 1   0
1 0 1 0   0
1 0 1 1   0
1 1 0 0   0
1 1 0 1   0
1 1 1 0   1
1 1 1 1   0

Output O3 (registered)

O2 O3 O4 I2   O3
0 0 0 0   0
0 0 0 1   0
0 0 1 0   0
0 0 1 1   0
0 1 0 0   1
0 1 0 1   0
0 1 1 0   1
0 1 1 1   0
1 0 0 0   1
1 0 0 1   0
1 0 1 0   1
1 0 1 1   0
1 1 0 0   0
1 1 0 1   0
1 1 1 0   1
1 1 1 1   0

Output O4 (registered)

O2 O3 O4 I2   O4
0 0 0 0   0
0 0 0 1   0
0 0 1 0   1
0 0 1 1   0
0 1 0 0   0
0 1 0 1   0
0 1 1 0   1
0 1 1 1   0
1 0 0 0   0
1 0 0 1   0
1 0 1 0   1
1 0 1 1   0
1 1 0 0   1
1 1 0 1   0
1 1 1 0   1
1 1 1 1   0

Output O5 (registered)

O2 O3 O4 I2   O5
0 0 0 0   1
0 0 0 1   1
0 0 1 0   0
0 0 1 1   1
0 1 0 0   1
0 1 0 1   1
0 1 1 0   1
0 1 1 1   1
1 0 0 0   1
1 0 0 1   1
1 0 1 0   0
1 0 1 1   1
1 1 0 0   0
1 1 0 1   1
1 1 1 0   1
1 1 1 1   1

Output O6 (registered)

O2 O3 O4 I2   O6
0 0 0 0   1
0 0 0 1   1
0 0 1 0   1
0 0 1 1   1
0 1 0 0   1
0 1 0 1   1
0 1 1 0   0
0 1 1 1   1
1 0 0 0   1
1 0 0 1   1
1 0 1 0   0
1 0 1 1   1
1 1 0 0   1
1 1 0 1   1
1 1 1 0   0
1 1 1 1   1

Output O7 (registered)

I3 I4   O7
0 0   0
0 1   1
1 0   1
1 1   0

Output IO8 (combinatorial)

O2 O3 O4 I1   IO8
0 0 0 0   1
0 0 0 1   0
0 0 1 0   0
0 0 1 1   0
0 1 0 0   1
0 1 0 1   0
0 1 1 0   0
0 1 1 1   0
1 0 0 0   1
1 0 0 1   0
1 0 1 0   0
1 0 1 1   0
1 1 0 0   1
1 1 0 1   0
1 1 1 0   1
1 1 1 1   1