4554 Datasheet, PDF (70/138 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

4554 Group
LCD control register L1
at reset : 00002
at power down : state retained
R/W
TAL1/TL1A
Internal dividing resistor for LCD power
L13
supply selection bit (Note 2)
0
2r ✕ 3, 2r ✕ 2
1
r ✕ 3, r ✕ 2
L12
LCD control bit
0
Off
1
On
L11
LCD duty and bias selection bits
L10
L11 L10
00
01
10
11
Duty
Bias
Not available
1/2
1/2
1/3
1/3
1/4
1/3
LCD control register L2
at reset : 00002
at power down : state retained
L23 VLC3/SEG0 pin function switch bit (Note 3)
0
SEG0
1
VLC3
L22 VLC2/SEG1 pin function switch bit (Note 4)
0
SEG1
1
VLC2
L21 VLC1/SEG2 pin function switch bit (Note 4)
0
SEG2
1
VLC1
L20
Internal dividing resistor for LCD power
supply control bit
0
Internal dividing resistor valid
1
Internal dividing resistor invalid
W
TL2A
LCD control register L3
at reset : 00002
SEG24/P33–SEG27/P30 pin function
L33
switch bit
SEG28/P23, SEG29/P22 pin function
L32
switch bit
SEG30/P21 pin function
L31
switch bit
SEG31/P20 pin function
L30
switch bit
0
SEG24–SEG27
1
P33–P30
0
SEG28, SEG29
1
P23, P22
0
SEG30
1
P21
0
SEG31
1
P20
Notes 1: “R” represents read enabled, and “W” represents write enabled.
2: “r (resistor) multiplied by 3” is used at 1/3 bias, and “r multiplied by 2” is used at 1/2 bias.
3: VLC3 is connected to VDD internally when SEG0 pin is selected.
4: Use internal dividing resistor when SEG1 and SEG2 pins are selected.
at power down : state retained
W
TL3A
Rev.3.00 Aug 06, 2004 page 70 of 136
REJ03B0043-0300Z