Datasheet

Section 9 I/O Ports
Rev.6.00 Sep. 27, 2007 Page 404 of 1268
REJ09B0220-0600
9.9 Port B
9.9.1 Overview
Port B is an 8-bit I/O port. Port B has an address bus output function, and the pin functions change
according to the operating mode.
Port B has a built-in MOS input pull-up function that can be controlled by software.
Figure 9.8 shows the port B pin configuration.
PB
7
/ A
15
PB
6
/ A
14
PB
5
/ A
13
PB
4
/ A
12
PB
3
/ A
11
PB
2
/ A
10
PB
1
/ A
9
PB
0
/ A
8
PB
7
(input) / A
15
(output)
PB
6
(input) / A
14
(output)
PB
5
(input) / A
13
(output)
PB
4
(input) / A
12
(output)
PB
3
(input) / A
11
(output)
PB
2
(input) / A
10
(output)
PB
1
(input) / A
9
(output)
PB
0
(input) / A
8
(output)
Port B pins
Pin functions in mode 6
Pin functions in mode 7
A
15
(output)
A
14
(output)
A
13
(output)
A
12
(output)
A
11
(output)
A
10
(output)
A
9
(output)
A
8
(output)
Pin functions in modes 4 and 5
PB
7
(I/O)
PB
6
(I/O)
PB
5
(I/O)
PB
4
(I/O)
PB
3
(I/O)
PB
2
(I/O)
PB
1
(I/O)
PB
0
(I/O)
Port B
Figure 9.8 Port B Pin Functions