HD64F2638F20J Datasheet, PDF (312/1512 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 9 I/O Ports
H8S/2639, H8S/2638, H8S/2636,
H8S/2630, H8S/2635 Group
Port B Data Register (PBDR)
Bit
:
Initial value :
R/W
:
7
PB7DR
0
R/W
6
PB6DR
0
R/W
5
PB5DR
0
R/W
4
PB4DR
0
R/W
3
PB3DR
0
R/W
2
PB2DR
0
R/W
1
PB1DR
0
R/W
0
PB0DR
0
R/W
PBDR is an 8-bit readable/writable register that stores output data for the port B pins (PB7 to
PB0). PBDR is initialized to H'00 by a reset, and in hardware standby mode. It retains its prior
state in software standby mode.
Port B Register (PORTB)
Bit
:
7
6
5
4
3
2
1
0
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
Initial value : —^*
—^*
—^*
—^*
—^*
—^*
—^*
—^*
R/W
:R
R
R
R
R
R
R
R
Note: * Determined by state of pins PB7 to PB0.
PORTB is an 8-bit read-only register that shows the pin states. It cannot be written to. Writing of
output data for the port B pins (PB7 to PB0) must always be performed on PBDR.
If a port B read is performed while PBDDR bits are set to 1, the PBDR values are read. If a port B
read is performed while PBDDR bits are cleared to 0, the pin states are read.
After a reset and in hardware standby mode, PORTB contents are determined by the pin states, as
PBDDR and PBDR are initialized. PORTB retains its prior state in software standby mode.
Page 262 of 1458
REJ09B0103-0800 Rev. 8.00
May 28, 2010