Datasheet

Section 9 I/O Ports
Rev.5.00 Nov. 02, 2005 Page 125 of 500
REJ09B0027-0500
9.4.4 Port Pull-Up Control Register 5 (PUCR5)
PUCR5 controls the pull-up MOS in bit units of the pins set as the input ports.
Bit Bit Name
Initial
Value R/W Description
7, 6 All 0 Reserved
These bits are always read as 0.
5
4
3
2
1
0
PUCR55
PUCR54
PUCR53
PUCR52
PUCR51
PUCR50
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
Only bits for which PCR5 is cleared are valid. The pull-up
MOS of the corresponding pins enter the on-state when
these bits are set to 1, while they enter the off-state when
these bits are cleared to 0.
9.4.5 Pin Functions
The correspondence between the register specification and the port functions is shown below.
P57/SCL pin
Register ICCR1 PCR5
Bit Name ICE PCR57 Pin Function
Setting Value 0 0 P57 input pin
1 P57 output pin
1 X SCL I/O pin
Legend: X: Don't care.
SCL performs the NMOS open-drain output, that enables a direct bus drive.