Datasheet

Section 9 I/O Ports
Rev. 1.50 Sep. 18, 2007 Page 161 of 584
REJ09B0240-0150
Port E has the following registers.
• Port control register E (PCRE)
• Port data register E (PDRE)
9.9.1 Port Control Register E (PCRE)
PCRE selects inputs/outputs in bit units for pins to be used as general I/O ports of port E.
Bit Bit Name
Initial
Value R/W Description
7
6
5
4
3
2
1
0
PCRE7
PCRE6
PCRE5
PCRE4
PCRE3
PCRE2
PCRE1
PCRE0
0
0
0
0
0
0
0
0
W
W
W
W
W
W
W
W
When each of the port E pins functions as a general I/O
port, setting a PCRE bit to 1 makes the corresponding
pin an output port, while clearing the bit to 0 makes the
pin an input port.
9.9.2 Port Data Register E (PDRE)
PDRE is a general I/O port data register of port E.
Bit Bit Name
Initial
Value R/W Description
7
6
5
4
3
2
1
0
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PDRE stores output data for port E pins.
If PDRE is read while PCRE bits are set to 1, the
values stored in PDRE are read. If PDRE is read while
PCRE bits are cleared to 0, the pin states are read
regardless of the value stored in PDRE.