HD6432646 Hitachi, HD6432646 Datasheet - Page 671

• Manufacturer Part Number: HD6432646
• Description: (HD64F264x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

18.2.2
LCR is an 8-bit read/write register which performs LCD power supply split-resistance connection
control and display data control, and selects the frame frequency.
LCR is initialized to H'80 upon reset and in standby mode.
Bit 7—Reserved: This bit is always read as 1 and cannot be modified.
Bit 6—LCD Power Supply Split-Resistance Connection Control (PSW): Bit 6 can be used to
disconnect the LCD power supply split-resistance from V
power-down mode, or when an external power supply is used. When the ACT bit is cleared to 0,
and also in standby mode, the LCD power supply split-resistance is disconnected from V
regardless of the setting of this bit.
Bit 6: PSW
0
1
Bit 5—Display Function Activate (ACT): Bit 5 specifies whether or not the LCD
controller/driver is used. Clearing this bit to 0 halts operation of the LCD controller/driver. The
LCD drive power supply ladder resistance is also turned off, regardless of the setting of the PSW
bit. However, register contents are retained.
Bit 5: ACT
0
1
Bit 4—Display Data Control (DISP): Bit 4 specifies whether the LCD RAM contents are
displayed or blank data is displayed regardless of the LCD RAM contents.
Bit 4: DISP
0
1
Bit
Initial value
Read/Write
LCD Control Register (LCR)
Description
LCD power supply split-resistance is disconnected from V
LCD power supply split-resistance is connected to V
Description
LCD controller/driver operation halted
LCD controller/driver operates
Description
Blank data is displayed
LCD RAM data is display
—
—
7
1
PSW
R/W
6
0
ACT
R/W
5
0
DISP
R/W
4
0
CC
CKS3
when LCD display is not required in a
R/W
3
0
CC
CKS2
R/W
2
0
CC
CKS1
R/W
1
0
(Initial value)
(Initial value)
(Initial value)
CC
CKS0
R/W
0
0
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