Getting second line to work on GDM1602K LCD?

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1

Recently I bought this 16x2 GDM1602K LCD to use with my Arduino.

http://www.sparkfun.com/commerce/produc … ts_id=709#

I am using this 4-bit library with it and it works well.

http://www.arduino.cc/playground/Code/LCD4BitLibrary

For the first line at least. The problem is that I can not seem to figure out how to make this display go to the second line.

Does anyone have any experience with this LCD that can help me?

Thanks!

2

As far as Character LCDs usually go, they treat the display as an 80x1 or a 40x2 display regardless of the number of characters on the LCD itself.

You should find that since your display is a 2-Line unit the 2nd line will start at memory address 40 (0x28 in hex) so you need to write your 2nd line starting there.

3

When I set it to start at 0x28 it still goes on the first line. It will wrap around but not perfectly as it takes a few second for the message to get to the bottom.

I think the trick is in this initializing code

LcdCommandWrite(0x2C); // function set:
// 4-bit interface, 1 display lines, 5x7 font

I don’t know how I would change it to 1 line though.