Datasheet

Rev.6.00 Oct.28.2004 page 307 of 1016
REJ09B0138-0600H
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 on-chip MOS input pull-up function that can be controlled by software (on-chip ROM version only).
Figure 9-11 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
PB
6
PB
5
PB
4
PB
3
PB
2
PB
1
PB
0
Note: * Modes 6 and 7 are provided in the on-chip ROM version only.
(input)/
(input)/
(input)/
(input)/
(input)/
(input)/
(input)/
(input)/
A
15
A
14
A
13
A
12
A
11
A
10
A
9
A
8
(output)
(output)
(output)
(output)
(output)
(output)
(output)
(output)
Port B pins
Pin functions in mode 6*
Pin functions in mode 7*
A
15
A
14
A
13
A
12
A
11
A
10
A
9
A
8
(output)
(output)
(output)
(output)
(output)
(output)
(output)
(output)
Pin functions in modes 4 and 5
PB
7
PB
6
PB
5
PB
4
PB
3
PB
2
PB
1
PB
0
(I/O)
(I/O)
(I/O)
(I/O)
(I/O)
(I/O)
(I/O)
(I/O)
Port B
Figure 9-11 Port B Pin Functions