SAM4L Datasheet, PDF (1032/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

Figure 39-6. Driving a LCD With Three Common Lines
ATSAM4L4/L2
39.6.2.4
1/4 Duty and 1/3 Bias
1/3 bias is optimal for LCD with four common terminals (1/4 duty). SEG0-COM0 is the voltage
across a segment that is ON and SEG0-COM1 is the voltage across a segment that is OFF.
Figure 39-7. Driving a LCD With Four Common Lines
VLCD
2/3 VLCD
1/3 VLCD
GND
VLCD
2/3 VLCD
1/3 VLCD
GND
VLCD
2/3 VLCD
1/3 VLCD
GND
-1/3 VLCD
-2/3 VLCD
- VLCD
Frame
Frame
SEG0
COM0
VLCD
2/3 VLCD
1/3 VLCD
GND
VLCD
2/3 VLCD
1/3 VLCD
GND
SEG0-COM0
VLCD
2/3 VLCD
1/3 VLCD
GND
-1/3 VLCD
-2/3 VLCD
- VLCD
Frame
SEG0
COM1
SEG0-COM1
Frame
39.6.3
Enabling/Disabling LCDCA
Write bit Enable (EN) to one in Control Register (CR) to enable the module. Write bit Disable
(DIS) to one to disable it. LCD controller will be disabled after the completion of current frame.
Bit Enable in Status Register (SR.EN) is set to one when LCD controller is ready to operate and
set to zero when LCD power supply is off.
42023C–SAM–02/2013
1032