gt911 — Touch Screen Driver

Basic polling mode example usage:

import time
from gt911 import GT911
from machine import I2C
# Note use pin numbers or names not Pin objects because the
# driver needs to change pin directions to reset the controller.
touch = GT911(I2C(1, freq=400_000), reset_pin="P1", irq_pin="P2", touch_points=5)
while True:
   n, points = touch.read_points()
   for i in range(0, n):
      print(f"id {points[i][3]} x {points[i][0]} y {points[i][1]} size {points[i][2]}")
   time.sleep_ms(100)

Constructors

class gt911.GT911(bus: int, reset_pin, irq_pin, address=0x5D, width=800, height=480, touch_points=1, reserve_x=False, reserve_y=False, reverse_axis=True, stio=True, refresh_rate=240, touch_callback=None)

Creates a touch screen controller object. You should initialize it according to the example above.

Methods

GT911._read_reg(reg: int, size=1, buf=None)

Reads a register value.

GT911._write_reg(reg: int, val: int, size=1)

Writes a register value.

GT911.read_id() → int

Returns the ID of the gt911 chip.

GT911.read_points()

Returns a tuple containing the count of points an array of point tuples. Each point tuple has an x[0], y[1], size[2], and id[3]. x/y are the position on screen. Size is the amount of pressure applied. And id is a unique id per point which should correlate to the same point over reads.

GT911.reset() → None

Resets the gt911 chip.