Datasheet

Section 8 I/O Ports
Rev. 2.00 Sep. 28, 2009 Page 186 of 870
REJ09B0429-0200
8.1.4 Pin Functions
The relationship between the register settings and the pin function is shown below.
(1) Extended Mode (EXPE = 1)
The pin function is switched as shown below according to the P1nDDR bit.
P1nDDR 0 1
ADMXE 0 1 0 1
ABW,
ABW256
X Either bit is 0
(8/16-bit bus)
Both bits
are 1 (8-bit
bus)
X Either bit is 0
(8/16-bit
bus)
Both bits
are 1 (8-bit
bus)
Pin
function
P1n input
pin
ADn
input/output
pin
P1n input
pin
An output
pin
Setting
prohibited
P1n output
pin
[Legend] n = 7 to 0, X: Don't care.
(2) Single-Chip Mode (EXPE = 0)
The pin function is switched as shown below according to the P1nDDR bit.
P1nDDR 0 1
Pin function P1n input pin P1n output pin
[Legend] n = 7 to 0
8.1.5 Port 1 Input Pull-Up MOS
Port 1 has built-in input pull-up MOSs that can be controlled by software. The input pull-up MOS
can be used regardless of the operating mode. Table 8.2 summarizes the input pull-up MOS states.
Table 8.2 Port 1 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 P1DDR = 0 and P1PCR = 1; otherwise off.