Panasonic MN101C77C - Manual (Page 169)

IV - 19
Chapter 4 I/O Ports
Port 2
Figure 4-4-2 Block Diagram (P20, P22 to P24)
4-4-3 Block Diagram
Figure 4-4-3 Block Diagram (P21)
R
D
L
Q
Reset
Write Read
Read
Pull-up resistor control
Port input data
P2PLU0,2-4
P2IN0,2-4
P20,P22-P24
External interrupt
Schmitt trigger input
R
D
L
Q
Reset
Write Read
D
L
Q
Write Read
R
Reset
I/O direction control
Port outut data
Data bus
P2DIR0,2-4
P2OUT0,2-4
R
D
L
Q
Reset
Write Read
Read
Pull-up resistor control
Port input data
NFCTR register bp7
AC zero-cross
detection circuit
M
U
X
P2PLU1
P2IN1
1
0
P21
AC zero-cross input
External intrerrupt
Schmitt trigger input
R
D
L
Q
Reset
Write Read
D
L
Q
Write Read
R
Reset
I/O direction control
Port output data
Data bus
P2DIR1
P2OUT1