
120
Table 7-1 Port Functions (1)
Port
Description
Pins
Mode 1
Mode 2
Mode 3
Port 1
8-bit I/O port
Can drive LEDs
P1
7
to P1
0
/
A
7
to A
0
Address output (A
7
to
A
0
) and generic input
DDR = 0:
generic input
DDR = 1:
address output
Generic input/output
Port 2
8-bit I/O port
Input pull-up
Can drive LEDs
P2
7
to P2
0
/
A
15
to A
8
Address output (A
15
to
A
8
) and generic input
DDR = 0:
generic input
DDR = 1:
address output
Generic input/output
Port 3
8-bit I/O port
P3
7
to P3
0
/
D
7
to D
0
P5
3
to P5
0
/
A
19
to A
16
Data input/output (D
15
to D
8
)
Address output (A
19
to
A
16
) and generic input
DDR = 0:
generic input
DDR = 1:
address output
Generic input/output
Port 5
4-bit I/O port
Input pull-up
Can drive LEDs
Generic input/output
Port 6
4-bit I/O port
P6
5
/
WR
,
P6
4
/
RD
,
P6
3
/
AS
P6
0
/
WAIT
Bus control signal
output (
WR
,
RD
,
AS
)
Generic input/output
Bus control signal
output (
WAIT
) and
1-bit generic input/
output
Port 7
8-bit input port
P7
7
to P7
0
/
AN
7
to AN
0
P8
3
/IRQ
3
,
P8
2
/IRQ
2
,
P8
1
/IRQ
1
P8
0
/IRQ
0
P9
4
/SCK/IRQ
4
Analog input (AN
7
to AN
0
) to A/D converter, and generic input
Port 8
4-bit I/O port
P8
2
to P8
0
have
Schmitt inputs
IRQ
3
to IRQ
0
input and 4-bit generic input/output
Port 9
3-bit I/O port
Input and output (SCK) for serial communication interface
(SCI), IRQ
4
input, and 1-bit generic input/output
Input and output (RxD and Txd) for SCI and 2-bit generic
input/output
P9
2
/RxD,
P9
0
/TxD