SH7751 Datasheet, PDF (860/1224 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

18. I/O Ports
Bit 2n + 1 (n = 0–15)—Port Pull-Up Control (PBnPUP): Specifies whether each bit in the 16-
bit port B is to be pulled up with a built-in resistor. Pull-up is automatically turned off for a port
pin set to output by bit PBnIO.
Bit 2n + 1: PBnPUP
0
1
Description
Bit m (m = 16–31) of 16-bit port B is pulled up
Bit m (m = 16–31) of 16-bit port B is not pulled up
(Initial value)
Bit 2n (n = 0–15)—Port I/O Control (PBnIO): Specifies whether each bit in the 16-bit port B is
an input or an output.
Bit 2n: PBnIO
0
1
Description
Bit m (m = 16–31) of 16-bit port B is an input
Bit m (m = 16–31) of 16-bit port B is an output
(Initial value)
18.2.4 Port Data Register B (PDTRB)
Port data register B (PDTRB) is a 16-bit readable/writable register used as a data latch for each bit
in the 16-bit port B. When a bit is set as an output, the value written to the PDTRB register is
output from the external pin. When a value is read from the PDTRB register while a bit is set as an
input, the external pin value sampled on the external bus clock is read. When a bit is set as an
output, the value written to the PDTRB register is read.
PDTRB is not initialized by a power-on or manual reset, or in standby mode, and retains its
contents.
Bit: 15
14
13
12
11
10
9
8
PB31DT PB30DT PB29DT PB28DT PB27DT PB26DT PB25DT PB24DT
Initial value: —
—
—
—
—
—
—
—
R/W: R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit:
7
6
5
4
3
2
1
0
PB23DT PB22DT PB21DT PB20DT PB19DT PB18DT PB17DT PB16DT
Initial value: —
—
—
—
—
—
—
—
R/W: R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Rev.4.00 Oct. 10, 2008 Page 762 of 1122
REJ09B0370-0400