CHAPTER 4 PORT FUNCTIONS
User’s Manual U15331EJ4V1UD
85
Figure 4-10. Block Diagram of P34
(a) When
µ
PD789488, 78F9488 is used
P34
WR
PUB3
RD
WR
PORT
WR
PM
PUB34
PM34
V
DD
P-ch
Internal bus
Selector
Output latch
(P34)
(b) When
µ
PD789489, 78F9489 is used
P34/RIN
WR
PUB3
RD
WR
PORT
WR
PM
PUB34
PM34
V
DD
P-ch
Internal bus
Selector
Output latch
(P34)
Alternate
function
PUB3: Pull-up resistor option register B3
PM:
Port mode register
RD:
Port 3 read signal
WR:
Port 3 write signal