Datasheet
Section 9 I/O Ports 
Rev. 3.00 Mar. 15, 2006 Page 126 of 526 
REJ09B0060-0300   
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 
 
 
0 
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 MOSs 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 ICCR 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. 










