Mandar Joshi
Member level 2
How to map COM & segment terminals of segment LCD in order to display 0-9 numbers?
I have interfaced ATxmega64B1 with segment LCD(VI-302-DP-FC-S-LV) having 29 segments and 2 COM pins.
As the XMEGA manual says, the LCD controller can automatically handle ASCII characters. Instead of setting and clearing segments of the digit, the user enters the ASCII code and the Digit Decoder updates itself the corresponding segment values in the Display Memory. And for that four types of ASCII character mapping is supported, which includes
1. 3 COM term and 3 SEG term
2. 4 COM term and 2 SEG term
3. 4 COM term and 4 SEG term
4. 3 COM term and 6 SEG term
But my LCD is having only 2 COM terminals. So in order to display the numbers from 0-9 do I need to write corresponding look-up table for every digit as we do in Seven Segment Display or do I need to write the corresponding ASCII code for number?
Also, register CTRLG in LCD module contains the bit fields which specify Type of Digit and Start Segment what combination of these bit fields should I write for my display?
Do I need to use DECODE[6:0] bit field in CTRLH register to mention particular display pattern every time?
What are the pixel calculations in Data register in LCD module?
The LCD schematic is as follows. Rest of controller side pins for LCD are unconnected(i.e. used as GPIO as given in datasheet).
I have interfaced ATxmega64B1 with segment LCD(VI-302-DP-FC-S-LV) having 29 segments and 2 COM pins.
As the XMEGA manual says, the LCD controller can automatically handle ASCII characters. Instead of setting and clearing segments of the digit, the user enters the ASCII code and the Digit Decoder updates itself the corresponding segment values in the Display Memory. And for that four types of ASCII character mapping is supported, which includes
1. 3 COM term and 3 SEG term
2. 4 COM term and 2 SEG term
3. 4 COM term and 4 SEG term
4. 3 COM term and 6 SEG term
But my LCD is having only 2 COM terminals. So in order to display the numbers from 0-9 do I need to write corresponding look-up table for every digit as we do in Seven Segment Display or do I need to write the corresponding ASCII code for number?
Also, register CTRLG in LCD module contains the bit fields which specify Type of Digit and Start Segment what combination of these bit fields should I write for my display?
Do I need to use DECODE[6:0] bit field in CTRLH register to mention particular display pattern every time?
What are the pixel calculations in Data register in LCD module?
The LCD schematic is as follows. Rest of controller side pins for LCD are unconnected(i.e. used as GPIO as given in datasheet).