Datasheet

CHAPTER 4 PORT FUNCTIONS
User’s Manual U18698EJ1V0UD
98
(3) Pull-up resistor option registers (PU1, PU3, PU4, PU10 to PU12, PU14, PU15)
These registers specify whether the on-chip pull-up resistors of P12, P13, P31 to P34, P40, P100, P101, P112,
P113, P120, P140 to P143, or P150 to P153 are to be used or not. On-chip pull-up resistors can be used in 1-bit
units only for the bits set to input mode of the pins to which the use of an on-chip pull-up resistor has been
specified in PU1, PU3, PU4, PU10 to PU12, PU14, and PU15. On-chip pull-up resistors cannot be connected to
bits set to output mode and bits used as alternate-function output pins, regardless of the settings of PU1, PU3,
PU4, PU10 to PU12, PU14, and PU15.
These registers can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation clears these registers to 00H.
Figure 4-18. Format of Pull-up Resistor Option Register
7Symbol
PU1
6543
PU13
2
PU12
1 0 Address
FF31H
After reset
00H
R/W
R/W
0
PU3
0 0 PU34 PU33 PU32 PU31
FF33H 00H R/W
PU4
PU40
FF34H 00H R/W
0
PU10
000
0 0 PU143 PU142
PU101 PU100 FF3AH 00H R/W
0
PU11
0 0 0 PU113 PU112 0 0
FF3BH 00H R/W
0
PU14
0 PU141 PU140
FF3EH 00H R/W
0
PU12
0 0 0 0 0 0 PU120
FF3CH 00H R/W
0 0 PU153 PU152
0
PU15
0 PU151 PU150
FF3FH 00H R/W
0000 00
0
0000000
00
PUmn
Pmn pin on-chip pull-up resistor selection
(m = 1, 3, 4, 10 to 12, 14, 15; n = 0 to 4)
0 On-chip pull-up resistor not connected
1 On-chip pull-up resistor connected