Gt911 Register Map -

Your X and Y are swapped or mirrored. The GT911 reports physical panel coordinates, not LCD coordinates. If you rotated your LCD via software, you must either:

This is almost always a threshold (0x8105) issue. If set too low (e.g., <30), environmental noise triggers false touches. Increase to 120 and test. gt911 register map

The GT911 (by Goodix) is a 5-point capacitive touch controller commonly found in displays (LCDs, LVDS, HDMI panels). Understanding its register map is key for debugging, calibration, or bare-metal drivers. Your X and Y are swapped or mirrored

You cannot write to the configuration registers while the GT911 is in active mode at 0x5D. Use this sequence: Enter Config Mode: Write to I²C address 0x14

Enter Config Mode: Write to I²C address 0x14. Any write to 0x14 unlocks configuration.

Write Config Array: Start at 0x8100 and write 184 bytes (entire configuration block). Crucially, the last byte must be a checksum!

Calculate Checksum: Sum of bytes from 0x8100 to 0x81B6 (all config bytes except the checksum itself), modulo 256, then 0xFF - (sum % 256) + 1.

Write Checksum to 0x81B7.

Soft Reset: Write 0x01 to register 0x804E (Soft Reset command). Wait 20ms.

Switch to Normal Mode: Change I²C address back to 0x5D. The GT911 is now operational.