Hitachi H8/3048 Hardware Manual page 274

Bits 7 to 4 are reserved. They cannot be modified and are always read as 1.
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P5DR is initialized to H'F0 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting.
Port 5 Input Pull-Up MOS Control Register (P5PCR): P5PCR is an 8-bit readable/writable
register that controls the MOS input pull-up MOS transistors in port 5.
Bit
—
Initial value
Read/Write —
In modes 5 to 7, when a P5DDR bit is cleared to 0 (selecting generic input), if the corresponding
bit from P5 PCR to P5
3
P5PCR is initialized to H'F0 by a reset and in hardware standby mode. In software standby mode
it retains its previous setting.
Table 9-9 summarizes the states of the input pull-ups MOS in each mode.
Table 9-9 Input Pull-Up MOS Transistor States (Port 5)
Mode Reset
1 Off
2
3
4
5 Off
6
7
Legend
Off: The input pull-up MOS transistor is always off.
On/off: The input pull-up MOS transistor is on if P5PCR = 1 and P5DDR = 0. Otherwise, it is off.
7 6 5
— —
1 1 1
— —
Reserved bits
PCR is set to 1, the input pull-up MOS transistor is turned on.
0
Hardware Standby Mode
Off
Off
4 3 2
— P5 PCR P5 PCR
3 2
1 0 0
— R/W R/W
Port 5 input pull-up MOS control 3 to 0
These bits control input pull-up MOS
transistors built into port 5
Software Standby Mode
Off
On/off
261
1 0
P5 PCR P5 PCR
1 0
0 0
R/W R/W
Other Modes
Off
On/off