Datasheet

Section 8 I/O Ports
Rev. 3.00 Sep. 28, 2009 Page 142 of 710
REJ09B0384-0300
• P43 to P40
The pin function is switched as shown below according to the P4nDDR bit.
When the ISSn bit in ISSR is cleared to 0 and the IRQnE bit in IER of the interrupt controller is
set to 1, this pin can be used as the IRQn input pin. To use this pin as the IRQn input pin, clear the
P4nDDR bit to 0.
P4nDDR 0 1
P4n input pin Pin function
IRQn input pin
P4n output pin
[Legend]
n = 3 to 0
8.4.8 Port 4 Input Pull-Up MOS
Port 4 has a built-in input pull-up MOS that can be controlled by software. This input pull-up
MOS can be used in single-chip mode. Table 8.5 summarizes the input pull-up MOS states.
Table 8.5 Port 4 Input Pull-Up MOS States
Reset
Hardware Standby
Mode
Software Standby
Mode
In Other Operations
Off Off On/Off On/Off
[Legend]
Off: Always off.
On/Off: On when input state and P4PCR = 1: otherwise off.