l58_touch.py - L58 Multi-Touch MicroPython Module

Tested on LilyGo-EPD47 T5 E-Paper 4.7" running MicroPython v1.18

Class L58Touch

L58Touch(bus, address):

Initialize the L58Touch controller.

Parameters:
    bus: SoftI2C object
    address: I2C address of the touch controller

Private Methods

_cmd_read(self, write, nbytes):

Write bytearray `write` to the controller then read `nbytes` bytes from the controller
and return the bytearray result.

Parameters:
    write: bytearray to write to the controller
    nbytes: number of bytes to read from the controller

Returns:
    bytearray: result of the read operation

_clear_flags(self):

Clear the touch controller flags

_append_point(self, point, point_data):

Parse `point` from `point_data` and append it to the touch_data list as a tuple.

Parameters:
    point: point number
    point_data: list of bytes from the controller

Format of `touch_data`: (finger, x, y, weight, status)
    finger: order of the point touched
    x: x coordinate of the point touched
    y: y coordinate of the point touched
    weight: weight/pressure of the point touched (1-15)
    status: status of the point touched (3 pressed, 0 released)
        Not all points will report released status during multi-touch.

Public Methods

scan_point(self):

scan the touch controller for touch points and update the touch_data list

Returns:
    int: number of points touched

get_point(self):

Return the last point in the touch_data list.

Point Format: (finger, x, y, weight, status)
    finger: order of the point touched
    x: x coordinate of the point touched
    y: y coordinate of the point touched
    weight: weight/pressure of the point touched (1-15)
    status: status of the point touched (3 pressed, 0 released)
        Not all points will report released status during multi-touch.

sleep(self):

Put the touch controller to sleep

wakeup(self):

Wake up the touch controller.
    Must be called to wake up the controller after sleep.

Example

from time import sleep
from machine import Pin, SoftI2C
import l58_touch

tp = l58_touch.L58Touch(SoftI2C(Pin(14), Pin(15)), 90)
while True:
    for _ in range(tp.scan_point()):
        if touch_point := tp.get_point():
            print(touch_point)
    sleep(0.1)