UPD78F9418AGK-9EU Renesas Electronics America, UPD78F9418AGK-9EU Datasheet - Page 86

• Manufacturer Part Number: UPD78F9418AGK-9EU
• Manufacturer: Renesas Electronics America

Specifications of UPD78F9418AGK-9EU

• Lead Free Status / Rohs Status: Supplier Unconfirmed

4.2.7 Port 9
mode register 9 (PM9). When using the P90 to P93 pins as input port pins, on-chip pull-up resistors can be connected
in 2-bit units by using pull-up resistor option register 2 (PU2).
84
This is a 4-bit I/O port with an output latch. Port 9 can be specified as input or output in 1-bit units by using port
Port 9 is also used to output segment signals for the LCD controller/driver.
Port 9 is set to input mode when the RESET signal is input.
Figure 4-14 shows a block diagram of port 9.
PU2:
PM:
RD:
WR:
LPS0:
n = 0, 2, m = 0 to 3
WR
WR
WR
WR
RD
PORT
PU2
LPS
PM
Pull-up resistor option register 2
Port mode register
Port 9 read signal
Port 9 write signal
LCD port selector 0
Segment output
Output latch
PU29n
PM9m
(P9m)
LPS0
Figure 4-14. Block Diagram of P90 to P93
CHAPTER 4 PORT FUNCTIONS
User’s Manual U13952EJ3V1UD
V
DD0
P-ch
P90/S19 to P93/S16