M38203M4 Datasheet, PDF (242/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.7 LCD drive control circuit
2.7.2 Pins
SEG0–SEG15 are used as pins for LCD display. The pins P30/SEG16–P37/SEG23 and P00/SEG24–P07/
SEG31 and P10/SEG32–P17/SEG39 are available as segment output pins (SEG16–SEG39). By switching the
corresponding registers, the segment output pin, I/O pin or input pin is selected.
Table 2.7.1 shows the pin function by setting segment output enable register and Table 2.7.2 shows the
pin functions by setting the corresponding registers when they are not used as segment output pins.
Table 2.7.1 Pin functions by setting segment output enable register
Pins
Setting
Register
Value
Pin function
P30/SEG16
–P37/SEG23
SEG (Address 003816) b0
(Bit 0 of segment output enable register)
P00/SEG24,
P01/SEG25
SEG (Address 003816) b1
(Bit 1 of segment output enable register)
1
Segment output
0
Input port
1
Segment output
0
I/O port
P02/SEG26–
P07/SEG31
SEG (Address 003816) b2
(Bit 2 of segment output enable register)
P10/SEG32,
P11/SEG33
SEG (Address 003816) b3
(Bit 3 of segment output enable register)
1
Segment output
0
I/O port
1
Segment output
0
I/O port
P12/SEG34
SEG (Address 003816) b4
(Bit 4 of segment output enable register)
1
Segment output
0
I/O port
P13/SEG35–
P17/SEG39
SEG (Address 003816) b5
(Bit 5 of segment output enable register)
1
Segment output
0
I/O port
Note: When the microcomputer is in the reset state, the I/O or segment output pins are pulled down, so
that a “L” level is output from segment-only pins.
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3820 GROUP USER’S MANUAL