Bits 7 to 4 are reserved. They cannot be modified and are always read as 1.
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.
In modes 5 to 7, when a P5DDR bit is cleared to 0 (selecting generic input), if the corresponding
bit from P5
3
PCR to P5
0
PCR is set to 1, the input pull-up MOS transistor is turned on.
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
Hardware Standby Mode
Software Standby Mode
Other Modes
1
Off
Off
Off
Off
2
3
4
5
Off
Off
On/off
On/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.
Bit
Initial value
Read/Write
7
—
1
—
6
—
1
—
5
—
1
—
4
—
1
—
3
P5 PCR
0
R/W
3
2
P5 PCR
0
R/W
2
1
P5 PCR
0
R/W
1
0
P5 PCR
0
R/W
0
Reserved bits
These bits control input pull-up MOS
transistors built into port 5
Port 5 input pull-up MOS control 3 to 0
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