HD64F3028F25 Datasheet, PDF (286/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

8.3.2 Register Descriptions
Table 8.3 summarizes the registers of port 2.
Table 8.3 Port 2 Registers
Address^* Name
Initial Value
Abbreviation R/W Modes 1 to 4 Modes 5 to 7
H'EE001 Port 2 data direction register
P2DDR
W H'FF
H'00
H'FFFD1 Port 2 data register
P2DR
R/W H'00
H'00
H'EE03C Port 2 input pull-up MOS control P2PCR
register
R/W H'00
H'00
Note: * Lower 20 bits of the address in advanced mode.
Port 2 Data Direction Register (P2DDR): P2DDR is an 8-bit write-only register that can select
input or output for each pin in port 2.
Bit
7
6
5
4
3
2
1
0
P2₇DDR P2₆DDR P2₅DDR P2₄DDR P2₃DDR P2₂DDR P2₁DDR P2₀DDR
Modes ^{Initial value 1}
1
1
1
1
1
1
1
1 to 4 _{Read/Write —}
—
—
—
—
—
—
—
Modes ^{Initial value 0}
0
0
0
0
0
0
0
5 to 7 _{Read/Write W}
W
W
W
W
W
W
W
Port 2 data direction 7 to 0
These bits select input or
output for port 2 pins
Modes 1 to 4 (Expanded Modes with On-Chip ROM Disabled): P2DDR values are fixed at 1.
Port 2 functions as an address bus.
Mode 5 (Expanded Modes with On-Chip ROM Enabled): Following a reset, port 2 is an input
port. A pin in port 2 becomes an address output pin if the corresponding P2DDR bit is set to 1, and
a generic input port if this bit is cleared to 0.
Modes 6 and 7 (Single-Chip Mode): Port 2 functions as an input/output port. A pin in port 2
becomes an output port if the corresponding P2DDR bit is set to 1, and an input port if this bit is
cleared to 0.
In modes 1 to 4, P2DDR bits are always read as 1, and cannot be modified.
In modes 5 to 7, P2DDR is a write-only register. Its value cannot be read. All bits return 1 when
read.
Rev. 2.00, 09/03, page 254 of 890