HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 270

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

ABWCR and P4DDR are not initialized in software standby mode. When port 4 functions as a
generic input/output port, if a P4DDR bit is set to 1, the corresponding pin maintains its output
state in software standby mode.
Port 4 Data Register (P4DR): P4DR is an 8-bit readable/writable register that stores output data
for pins P4
corresponding P4DR bit is returned. When a bit in P4DDR is cleared to 0, if port 4 is read the
corresponding pin level is read.
P4DR is initialized to H'00 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting.
Port 4 Input Pull-Up MOS Control Register (P4PCR): P4PCR is an 8-bit readable/writable
register that controls the MOS input pull-up transistors in port 4.
Bit
Initial value
Read/Write
In mode 7 (single-chip mode), and in 8-bit bus mode in modes 1 to 6 (expanded modes), when a
P4DDR bit is cleared to 0 (selecting generic input), if the corresponding P4PCR bit is set to 1, the
input pull-up MOS transistor is turned on.
P4PCR is initialized to H'00 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting.
Bit
Initial value
Read/Write
7
to P4
P4 PCR
R/W
0
7
. When a bit in P4DDR is set to 1, if port 4 is read the value of the
7
0
R/W
P4
7
0
7
P4 PCR
R/W
6
6
0
R/W
P4
6
0
6
P4 PCR
Port 4 input pull-up MOS control 7 to 0
These bits control input pull-up MOS transistors built into port 4
R/W
5
5
0
R/W
P4
5
0
5
P4 PCR
Port 4 data 7 to 0
These bits store data for port 4 pins
R/W
257
4
4
0
R/W
P4
4
0
4
P4 PCR
R/W
3
3
0
R/W
P4
3
0
3
P4 PCR
R/W
2
2
0
R/W
P4
2
0
2
P4 PCR
R/W
1
1
0
R/W
P4
1
0
1
P4 PCR
R/W
0
0
0
R/W
P4
0
0
0