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Rev. 1.71
120
April 11, 2017
Rev. 1.71
121
April 11, 2017
HT66F002/HT66F0025/HT66F003/HT66F004
Cost-Effective A/D Flash MCU with EEPROM
HT66F002/HT66F0025/HT66F003/HT66F004
Cost-Effective A/D Flash MCU with EEPROM
LCD Bias Current Control
The LCD COM driver enables a range of selections to be provided to suit the requirement of the
LCD panel which are being used. The bias resistor choice is implemented using the ISEL1 and
ISEL0 bits in the SCOMC register.
SCOMC
Bit
7
6
5
4
3
2
1
0
Name
—
ISEL1
ISEL0
SCOMEN COM3EN COM2EN COM1EN COM0EN
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as “0”
Bit 6~5
ISEL1~ISEL0
: Select resistor for R type LCD bias current(V
DD
=5V)
00: 2×100kΩ (1/2 Bias), I
BIAS
= 25μA
01: 2×50 kΩ (1/2 Bias), I
BIAS
= 50μA
10: 2×25 kΩ (1/2 Bias), I
BIAS
= 100μA
11:
2×12.5 kΩ (1/2 Bias), I
BIAS
= 200μA
Bit 4
SCOMEN
: LCD control bit
0: Disable
1: Enable
When SCOMEN is set, it will turn on the DC path of resistor to generate 1/2 V
DD
bias voltage.
Bit 3
COM3EN
: PB3/AN7 or SCOM3 selection
0: PB3/AN7
1: SCOM3
Bit 2
COM2EN
: PB4/CLO or SCOM2 selection
0: PB4/CLO
1: SCOM2
Bit 1
COM1EN
: PC1 or SCOM1 selection
0: PC1
1: SCOM1
Bit 0
COM0EN
: PC0 or SCOM0 selection
0: PC0
1: SCOM0