Hi.

I am also trying to write the driver for the GT911 touchscreen controller for the RK043FN66HS-CTG by "Rocktech Displays". I also would like the c source code for this, please send to aihazelton@gmail.com

Can you please assist with how to configure and read the touch data?

I am communicating via I2C at 100 kbps and can send an receive data just fine. The programming manual and datasheet are quite vague as to how to set up the GT911. I need to use the GT911 in polling mode and only need to read one touch position at a time.

• When I touch the screen with 1 finger I the Status Register [0x814E] will read 0x81.
• When I touch the screen with 2 fingers I the Status Register [0x814E] will read 0x82.
• When I touch the screen with 0 fingers I the Status Register [0x814E] will read 0x00, not touched.

This is good as it means that the GT911 is working correctly, please see the attached waveform images.

1. But what do I need to write to the Real-time command (Write only) registers [0x8040 to 0x8100] for the RK043FN66HS-CTG?
2. What mode is the GT911 supposed to be in (Receive mode, Slave Approach mode) ?
3. Which registers do is read the touch point x and y coordinates from? The following registers just give the same values over and over, regardless of whether the screen is being touched or not.

0x8158 - Point 1 x coordinate (low byte)

0x8159 - Point 1 x coordinate (high byte)

0x815A - Point 1 y coordinate (low byte)

0x815B - Point 1 y coordinate (high byte)