M38203M4 Datasheet, PDF (246/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.7 LCD drive control circuit
(1) Segment output enable register (address 003816)
The pins P30/SEG16–P37/SEG23, P00/SEG24–P07/SEG31, P10/SEG32–P17/SEG39 can be used as segment
output pins by setting bits 0 to 5 of the segment output enable register (address 003816).
The pins corresponding to the bits which are set to “1” among bits 0 to 5 of the segment output enable
register (address 003816) are used as segment output pins. The pins corresponding to the bits which
are set to “0” are used as I/O ports or input ports.
Figure 2.7.2 shows the structure of the segment output enable register.
Segment output enable register
b7 b6 b5 b4 b3 b2 b1 b0
00
Segment output enable register (SEG) [Address 3816]
B
Name
0 ^{Segment output}
enable bit 0
1 ^{Segment output}
enable bit 1
2 ^{Segment output}
enable bit 2
Functions
At reset R W
0: Input ports P30–P37
0
1: Segment output SEG16–SEG23
0: I/O ports P00, P01
0
1: Segment output SEG24, SEG25
0: I/O ports P02–P07
0
1: Segment output SEG26–SEG31
3 Segment output ^{0: I/O ports P10, P11}
0
enable bit 3
1: Segment output SEG32, SEG33
4 ^{Segment output 0: I/O port P12}
0
enable bit 4
1: Segment output SEG34
5 ^{Segment output 0: I/O ports P13–P17}
0
enable bit 5
1: Segment output SEG35–SEG39
6,7 Fix these bits to “0.”
0 00
Fig. 2.7.2 Structure of segment output enable register
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3820 GROUP USER’S MANUAL