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CHAPTER 12 PORT FUNCTION
(1) Function of each port
The ports of the V853 have the functions shown in the table below.
Each port can be manipulated in 8- or 1-bit units and perform various types of control operations. In addition
to port functions, the ports also have functions as internal hardware input/output pins, when placed in the
control mode.
Port Name
Port Function
Function in Control Mode
Remarks
Port 0
8-bit I/O port
Can be set in the
input or output mode
in 1-bit units.
(Port 6 is a 4-bit port.)
Real-time pulse unit (RPU) input/output
External interrupt input
A/D converter external trigger input
Can be set in port or control
mode in 1-bit units.
Port 1
Real-time pulse unit (RPU) input/output
External interrupt input
Serial interface (CSI2) input/output
Port 2
PWM0, PWM1 output
Serial interface (UART0/CSI0, UART1/CSI1)
input/output
Port 3
Real-time pulse unit (RPU) input/output
External interrupt input
Serial interface (CSI3) input/output
Port 4
Address/data bus (AD0 to AD7) for external memory
Can be set in port or control
Port 5
Address/data bus (AD8 to AD15) for external memory
mode in 8-bit units.
Port 6
Address bus (A16 to A19) for external memory
Can be set in port or control
mode in 2-bit units.
Port 7
8-bit input only port
A/D converter (ADC) analog input
—
Port 9
7-bit I/O port
Can be set in the
input or output mode
in 1-bit units.
Control signal output for external memory
Control signal input/output for system expansion
Can be set in port or control
mode in 5- or 1-bit units.
Port 11
8-bit I/O port
Can be set in the
input or output mode
in 1-bit units.
Real-time pulse unit (RPU) input/output
External interrupt input
Can be set in port or control
mode in 1-bit units.
Caution Be sure to follow the following steps of setting when switching the port that operates as an output
pin or an I/O pin in control mode, to the control mode.
<1> Set the inactive level of the signal output in the control mode to the relevant bit of port n
(Pn) (n = 0 to 6, 9 and 11).
<2> Switch to the control mode by the port n mode control register (PMCn).
If the above <1> is not executed, the contents of port n (Pn) may output momentarily when
switching from the port mode to the control mode.