Gt911 Register Map May 2026

If you’ve worked with capacitive touch screens on Raspberry Pi, ESP32, or STM32 projects, you’ve likely encountered the GT911. This popular touch controller from Goodix is everywhere—from cheap 7-inch LCD displays to industrial HMI panels.

While the driver code is often copy-pasted from GitHub, understanding the register map is what separates "it works" from "I can debug and optimize it."

Let’s pull back the curtain and map out the GT911’s internal memory.

Let’s walk through a minimal read sequence on an ESP32 or Arduino: gt911 register map

// Read number of touch points
uint8_t touch_count = 0;
i2c_read(0x5D, 0x8101, &touch_count, 1);
if(touch_count > 0)  touch_data[1];
uint16_t y = ((uint16_t)touch_data[4] << 8) 

The GT911 is one of the most popular capacitive touch panel controllers in the embedded world. Found in everything from Raspberry Pi touchscreens and DIY handheld gaming consoles to industrial HMIs and automotive displays, its popularity stems from its robust noise immunity, support for up to 5 simultaneous touches, and low cost. However, for engineers and hobbyists alike, the true power of the GT911 lies hidden within its register map. If you’ve worked with capacitive touch screens on

Accessing this map via I²C is the key to configuration, calibration, and raw data acquisition. This article provides an exhaustive deep dive into the GT911 register map, from basic addressing to advanced gesture recognition.

Let’s talk about Register 0x804C (Config Register #6). Bit 2 is the "Swap XY" bit. In a sane world, you set it to 1, the axes swap. In the GT911 world? It works, but it also affects the screen resolution registers (0x8048 and 0x804A).

If you hard-code a swap, but forget to swap your width/height registers, the touch point will be a mirror image across the diagonal. It’s a riddle wrapped in an enigma. The register map is logically laid out, but the interdependence of these bytes feels like a puzzle box. The GT911 is one of the most popular

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:

Typical startup config area (example offsets):

| Offset | Field | Typical value | |--------|-------|----------------| | 0x8048-0x804D | X/Y resolution | Depends on display | | 0x8060 | Touch threshold | 0x46 (70 raw) | | 0x8061 | Filter coefficient | 0x05 | | 0x807C | I2C watchdog | 0x09 (9 sec) |

Important: After writing config, write 0x00 to 0x80FE (soft reset) and send 0x01 to 0x8040 (config update flag).