Hitachi H8S/2645, Hardware Manual

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18.2 Register Descriptions
18.2.1 LCD Port Control Register (LPCR)
Bit 7 6 5 4 3 2 1 0
DTS1 DTS0 CMX — SGS3 SGS2 SGS1 SGS0
Initial value 0 0 0 0 0 0 0 0
Read/Write R/W R/W R/W — R/W R/W R/W R/W
LPCR is an 8-bit read/write register which selects the duty cycle, LCD driver, and pin functions.
LPCR is initialized to H'00 upon reset and in standby mode.
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 Bit 6:
DTS0 Bit 5:
CMX
Duty Cycle Common Drivers Notes
0 0 0 Static COM1 COM4, COM3, and COM2 can
be used as ports
(Initial value)
1 COM4 to COM1 COM4, COM3, and COM2 output
the same waveform as COM1
1 0 1/2 dutyCOM2 to COM1 COM4 and COM3 can be used
as ports
1 COM4 to COM1 COM4 outputs the same
waveform as COM3, and COM2
outputs the same waveform as
COM1
1 0 0 1/3 dutyCOM3 to COM1 COM4 can be used as a port
1 COM4 to COM1 Do not use COM4
1
*
1/4 dutyCOM4 to COM1 —
*
: Don’t care
Note: COM4 to COM1 function as ports when the setting of SGS3 to SGS0 is 0000 (initial value).
Bit 4—Reserved: This bit is always read as 0 and should only be written with 0.