M38203M4 Datasheet, PDF (89/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.1 I/O pins
Table 2.1.1 shows the memory allocation of
the port registers corresponding to each port.
Table 2.1.1 Memory allocation of port registers
Port
Port register address
P0
000016
P1
000216
P2
000416
P3
000616
P4
000816
P5
000A16
P6
000C16
P7
000E16
(2) Input/output switching of programmable I/O ports
Input/output switching of the programmable I/O ports is performed by the port direction register cor-
responding to each port (Note). Figure 2.1.2 shows the structure of the port Pi (i = 2, 4 to 7) direction
register, and Table 2.1.2 shows the memory allocation of the port direction registers corresponding to
each port. Figure 2.1.4 shows a port direction register setting example.
Note: In ports P0 and P1, input/output switching is performed by a port unit. By setting bit 0 of the
corresponding direction register to “0,” the port is set for the input mode. By setting to “1,” the
port is set for the output mode. Figure 2.1.3 shows the structure of the ports P0 and P1
direction registers.
Port Pi direction register
b7 b6 b5 b4 b3 b2 b1 b0
Port Pi direction register (PiD) (i = 2, 4 to 7)
[Address 0516, 0916, 0B16, 0D16, 0F16]
B
Name
0 Port Pi direction
register
Functions
0 : Port Pi0 input mode
1 : Port Pi0 output mode
At reset R W
0
×
1
0 : Port Pi1 input mode
0
×
1 : Port Pi1 output mode
2
0 : Port Pi2 input mode
0
×
1 : Port Pi2 output mode
3
0 : Port Pi3 input mode
0
×
1 : Port Pi3 output mode
4
0 : Port Pi4 input mode
0
×
1 : Port Pi4 output mode
5
0 : Port Pi5 input mode
0
×
1 : Port Pi5 output mode
6
0 : Port Pi6 input mode
0
×
1 : Port Pi6 output mode
7
0 : Port Pi7 input mode
0
×
1 : Port Pi7 output mode
Notes 1: Nothing is allocated bit 0 of port P4 direction register and bit 2
to bit 7 of port P7 direction register. These bits cannot be written
to.
2: The contents of the port Pi direction register cannot be read out
(refer to “2.1.4 Notes on use”).
Fig. 2.1.2 Structure of port Pi (i = 2, 4 to 7) direction register
3820 GROUP USER’S MANUAL
2–3