CHAPTER 14 PORT FUNCTIONS
User’s Manual U14359EJ4V0UM
466
14.3 Port Pin Functions
14.3.1 Port 0
Port 0 is an 8-bit I/O port that can be set to the input or output mode in 1-bit units.
7
6
5
4
3
2
1
0
Address
After reset
P0
P07
P06
P05
P04
P03
P02
P01
P00
FFFFF400H
Undefined
Bit position
Bit name
Function
7 to 0
P0n
(n = 7 to 0)
Port 0
I/O port
In addition to their function as port pins, the port 0 pins can also operate as real-time pulse unit (RPU) I/O, external
interrupt request inputs, PWM output, and DMA request inputs in the control mode.
(1) Operation in control mode
Port
Alternate Function
Remark
Block Type
P00
PWM0
PWM output
A
P01
INTP000/TI000
External interrupt request input/
Real-time pulse unit (RPU) input
P02
INTP001
External interrupt request input
B
P03
TO00
Real-time pulse unit (RPU) output
A
Port 0
P04 to P07
DMARQ0/INTP100 to
DMARQ3/INTP103
DMA request input/
external interrupt request input
H
(2) I/O mode/control mode setting
The port 0 I/O mode setting is performed by the port 0 mode register (PM0), and the control mode setting is
performed by the port 0 mode control register (PMC0) and the port 0 function control register (PFC0).
(a) Port 0 mode register (PM0)
This register can be read/written in 8-bit or 1-bit units.
7
6
5
4
3
2
1
0
Address
After reset
PM0
PM07
PM06
PM05
PM04
PM03
PM02
PM01
PM00
FFFFF420H
FFH
Bit position
Bit name
Function
7 to 0
PM0n
(n = 7 to 0)
Port Mode
Specifies input/output mode for P0n pin.
0: Output mode (output buffer on)
1: Input mode (output buffer off)