In the example below we assume SEG10 and COM1 and SEG4 in COM0 are the only segments
changed from frame to frame. Data are stored in r20 and r21 for simplicity
Assembly Code Example(1)
LCD_update:
; LCD Blanking and Low power waveform are unchanged.
; Update Display memory.
sts LCDDR0, r20
sts LCDDR6, r21
ret
C Code Example(1)
Void LCD_update(unsigned char data1, data2);
{
/* LCD Blanking and Low power waveform are unchanged. */
/* Update Display memory. */
LCDDR0 = data1;
LCDDR6 = data2;
}
Note:
Disabling the LCD
1. See ”About Code Examples” on page 9.
22.4.3
In some application it may be necessary to disable the LCD. This is the case if the MCU enters
Power-down mode where no clock source is present.
The LCD should be completely discharged before being disabled. No DC voltage should be left
across any segment. The best way to achieve this is to use the LCD Blanking feature that drives
all segment pins and common pins to GND.
When the LCD is disabled, port function is activated again. Therefore, the user must check that
port pins connected to a LCD terminal are either tri-state or output low (sink).
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ATmega169P
8018A–AVR–03/06
ATMEL [ ATMEL ]
