:mod:`gt911` --- Touch Screen Driver
====================================

.. module:: gt911
   :synopsis: 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
-------

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

   Reads a register value.

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

   Writes a register value.

.. method:: GT911.read_id() -> int

   Returns the ID of the gt911 chip.

.. method:: 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.

.. method:: GT911.reset() -> None

   Resets the gt911 chip.