int X = ( (regs[0x8012] & 0x0F) << 8 ) | regs[0x8011]; int Y = ( (regs[0x8014] & 0x0F) << 8 ) | regs[0x8013];
Understanding this map is essential for developers writing custom drivers or troubleshooting touch response issues in embedded systems.
If dragging your finger left moves the cursor right, adjust the flag bits inside Module Switch 1 (0x804D) or recalculate coordinates in your driver framework ( gt911 register map
Immediately after writing the checksum, you must write 0x01 to the to signal the controller to parse and apply the new configuration. 2. Coordinate Registers (0x8040 – 0x81A7)
Note: The GT911 automatically increments the register address pointer after each byte read, allowing for continuous reading of all coordinate data in one transaction. 4. Practical Implementation Tips int X = ( (regs[0x8012] & 0x0F) <<
| Offset | Register | Description | | :--- | :--- | :--- | | +0 | 0x8010 | – A rotating ID (0-31). Same ID across frames = same finger. | | +1 | 0x8011 | X Coordinate (Low Byte) – Bits 7-0 of X position | | +2 | 0x8012 | X Coordinate (High Byte) – Bits 11-8 of X position (not 15-12!). Only 12-bit resolution. | | +3 | 0x8013 | Y Coordinate (Low Byte) – Bits 7-0 of Y position | | +4 | 0x8014 | Y Coordinate (High Byte) – Bits 11-8 of Y position | | +5 | 0x8015 | Touch Size (Low Byte) – Area of contact (roughness) | | +6 | 0x8016 | Touch Size (High Byte) – Typically not used for basic apps |
Contains the version number of the configuration file. The chip will reject configuration writes if this value is lower than or equal to the current version in its internal flash, unless forced. Coordinate Registers (0x8040 – 0x81A7) Note: The GT911
The GT911 Register Map: The Digital Nervous System of Touch