455A Datasheet, PDF (48/148 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

455A Group
(6) LCD control register
• LCD control register L1
Register L1 controls duty/bias selection, LCD operation, internal
dividing resistor selection. Set the contents of this register
through register A with the TL1A instruction. The TAL1
instruction can be used to transfer the contents of register L1.
• LCD control register L2
Register L2 controls internal dividing resistor operation,
selection of pin functions; SEG0/VLC3, SEG1/VLC2, SEG2/VLC1.
Set the contents of this register through register A with the TL2A
instruction.
• LCD control register L3
Register L3 controls selection of pin functions; P20/SEG24 to
P23/SEG27. Set the contents of this register through register A
with the TL3A instruction.
• LCD control register C1
Register C1 controls selection of pin functions; P00/SEG16 to
P03/SEG19. Set the contents of this register through register A
with the TC1A instruction.
• LCD control register C2
Register C2 controls selection of pin functions; P10/SEG20 to
P13/SEG23. Set the contents of this register through register A
with the TC2A instruction.
• LCD control register C3
Register C3 controls selection of pin functions; P30/SEG28 to
P33/SEG31. The contents of this register through register A with
the TC3A instruction.
Table 19 LCD control registers (1)
LCD control register L1
L13
Internal dividing resistor for LCD power
supply selection bit (Note 2)
L12 LCD control bit
L11
LCD duty and bias selection bits
L10
at reset : 00002
0 2r × 3, 2r × 2
1 r × 3, r × 2
0 Stop (OFF)
1 Operating
L11 L1
at power down : state retained
R/W
TAL1/TL1A
Duty
Bias
0 0 Not available
Not available
0 1 1/2
1/2
1 0 1/3
1/3
1 1 1/4
1/3
LCD control register L2
L23 SEG0/VLC3 pin function switch bit (Note 3)
L22 SEG1/VLC2 pin function switch bit (Note 4)
L21 SEG2/VLC1 pin function switch bit (Note 4)
L20 ^{Internal dividing resistor for LCD power}
supply control bit
at reset : 00002
at power down : state retained
0 SEG0
1 VLC3
0 SEG1
1 VLC2
0 SEG2
1 VLC1
0 Internal dividing resistor valid
1 Internal dividing resistor invalid
LCD control register L3
at reset : 11112
at power down : state retained
L33 P23/SEG27 pin function switch bit
0 SEG27
1 P23
L32 P22/SEG26 pin function switch bit
0 SEG26
1 P22
L31 P21/SEG25 pin function switch bit
0 SEG25
1 P21
L30 P20/SEG24 pin function switch bit
0 SEG24
1 P20
Note 1.“R” represents read enabled, and “W” represents write enabled.
Note 2.“r (resistor) multiplied by 3” is used at 1/3 bias, and “r multiplied by 2” is used at 1/2 bias.
Note 3.VLC3 is connected to VDD internally when SEG0 pin is selected.
Note 4.Use internal dividing resistor when SEG1 and SEG2 pins are selected.
W
TL2A
W
TL3A
Rev.1.01 Feb 15, 2008 Page 48 of 146
REJ03B0224-0101