Datasheet

Section 10 I/O Ports
Rev.7.00 Mar. 18, 2009 page 489 of 1136
REJ09B0109-0700
• P30/TxD0/IrTxD
The pin function is switched as shown below according to the combination of bit TE in SCR of
SCI_0 and bit P30DDR.
TE 0 1
P30DDR 0 1 ⎯
Pin function P30 input P30 output
*
RxD0/IrRxD
output
*
Note: * NMOS open-drain output when P30ODR = 1.
10.4 Port 4
Port 4 is an 8-bit input-only port. Port 4 has the following register.
• Port 4 register (PORT4)
10.4.1 Port 4 Register (PORT4)
PORT4 is an 8-bit read-only register that shows port 4 pin states.
PORT4 cannot be modified.
Bit Bit Name Initial Value R/W Description
7 P47 ⎯* R
6 P46 ⎯* R
5 P45 ⎯* R
4 P44 ⎯* R
3 P43 ⎯* R
2 P42 ⎯* R
1 P41 ⎯* R
The pin states are always read from this register.
0 P40 ⎯* R
Note: * Determined by the states of pins P47 to P40.