HD6433802H Datasheet, PDF (316/435 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

13.2 Register Descriptions
13.2.1 LCD Port Control Register (LPCR)
Bit
Initial value
Read/Write
7
DTS1
0
R/W
6
DTS0
0
R/W
5
CMX
0
R/W
4
3
2
1
0
— SGS3 SGS2 SGS1 SGS0
—
0
0
0
0
W
R/W
R/W
R/W
R/W
LPCR is an 8-bit read/write register which selects the duty cycle and LCD driver pin functions.
Bits 7 to 5: Duty cycle select 1 and 0 (DTS1, DTS0), common function select (CMX)
The combination of DTS1 and DTS0 selects static, 1/2, 1/3, or 1/4 duty. CMX specifies whether
or not the same waveform is to be output from multiple pins to increase the common drive power
when not all common pins are used because of the duty setting.
Bit 7
DTS1
0
Bit 6
DTS0
0
Bit 5
CMX
0
1
0
1
0
1
1
0
0
1
1
1
0
1
Duty Cycle
Static
1/2 duty
1/3 duty
1/4 duty
Common Drivers Notes
COM₁ (initial value) Do not use COM₄, COM₃, and
COM₂.
COM₄ to COM₁
COM₄, COM₃, and COM₂ output
the same waveform as COM₁.
COM₂ to COM₁
Do not use COM₄ and COM₃.
COM₄ to COM₁
COM₄ outputs the same waveform
as COM₃, and COM₂ outputs the
same waveform as COM₁.
COM₃ to COM₁
Do not use COM₄.
COM₄ to COM₁
Do not use COM₄.
COM₄ to COM₁
—
Bit 4: Reserved bit
Bit 4 is reserved; only 0 can be written to this bit.
Bits 3 to 0: Segment driver select 3 to 0 (SGS3 to SGS0)
Bits 3 to 0 select the segment drivers to be used.
298