22.4 LCD Usage
The following section describes how to use the LCD.
22.4.1
LCD Initialization
Prior to enabling the LCD some initialization must be preformed. The initialization process nor-
mally consists of setting the frame rate, duty, bias and port mask. LCD contrast is set initially, but
can also be adjusted during operation.
Consider the following LCD as an example:
Figure 22-8. LCD usage example.
LCD
2a
1b
1c
2f
2b
2c
2g
2d
2e
51
50
49
SEG2
SEG1
SEG0
2f
2g
2d
..
2e
COM3 48
SEG0 47
SEG1 46
SEG2 45
2c
1b,1c
COM0
2a
2b
COM1
COM2
ATmega329
Connection table
Display:
TN Positive, Reflective
Number of common terminals:
Number of segment terminals:
Bias system:
3
21
1/3 Bias
1/3 Duty
3.0 0.3 V
Drive system:
Operating voltage:
240
ATmega169P
8018A–AVR–03/06
ATMEL [ ATMEL ]
