HD6473258CP10 Datasheet, PDF (91/301 Pages) Renesas Technology Corp – Hitachi Single-Chip Microcomputer

Pins of port 2 can drive a single TTL load and a 90-pF capacitive load when they are used as output
pins. They can also drive light-emitting diodes or a Darlington pair.
Table 5-5 details the port 2 registers.
Table 5-5. Port 2 Registers
Name
Abbreviation
Port 2 data direction register P2DDR
Port 2 data register
P2DR
Read/Write
W
R/W
Initial value
H’FF (mode 1)
H’00 (modes 2 and 3)
H’00
Address
H’FFB1
H’FFB3
Port 2 Data Direction Register (P2DDR)—H’FFB1
Bit
7
6
5
4
3
2
1
0
P27DDR P26DDR P25DDR P24DDR P23DDR P22DDR P21DDR P20DDR
Mode 1
Initial value
1
1
1
1
1
1
1
1
Read/Write
—
—
—
—
—
—
—
—
Modes 2 and 3
Initial value
0
0
0
0
0
0
0
0
Read/Write
W
W
W
W
W
W
W
W
P2DDR is an 8-bit register that selects the direction of each pin in port 2. A pin functions as an
output pin if the corresponding bit in P2DDR is set to 1, and as an input pin if the bit is cleared to 0.
Port 2 Data Register (P2DR)—H’FFB3
Bit
Initial value
Read/Write
7
6
5
4
3
2
1
0
P27
P26
P25
P24
P23
P22
P21
P20
0
0
0
0
0
0
0
0
R/W R/W R/W R/W R/W R/W R/W R/W
P2DR is an 8-bit register containing output data for pins P27 to P20, and controlling their input pull-
ups.
MOS Pull-Ups: Are available for input pins in modes 2 and 3. Software can turn on the MOS pull-
up by writing a 1 in P2DR, and turn it off by writing a 0. The pull-ups are automatically turned off
for output pins in modes 2 and 3, and for all pins in mode 1.
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