WhyCan Forum(哇酷开发者社区)

import struct
import time
from pyb import Pin, ExtInt, Switch
from machine import I2C
from micropython import schedule

import micropython
micropython.alloc_emergency_exception_buf(1000)

class GT911:
    def __init__(self, i2c, rst_label, int_label):
        self.i2c = i2c
        self.rst_pin = Pin(rst_label, Pin.OUT_PP)
        self.int_pin = Pin(int_label, Pin.OUT_PP)
        # Assert reset
        self.rst_pin.low()
        self.int_pin.low()
        time.sleep_ms(10)
        # Deassert reset
        self.rst_pin.high()
        # Wait until reset done
        time.sleep_ms(5)
        # Release INT pin for interrupt
        self.int_pin = Pin(int_label, Pin.PULL_UP)
        self.gt911_addr = 0x5D
    
    def read_reg(self, reg_addr, nbytes):
        return self.i2c.readfrom_mem(self.gt911_addr, reg_addr, nbytes, addrsize = 16)
    
    def write_reg(self, reg_addr, data):
        self.i2c.writeto_mem(self.gt911_addr, reg_addr, data, addrsize = 16)
    
    def get_touch_point(self, id):
        info = self.i2c.readfrom_mem(self.gt911_addr, 0x8148 + id * 0x8, 0x8, addrsize = 16)
        return tuple([struct.unpack('<h', info[0:2])[0], struct.unpack('<h', info[2:4])[0], struct.unpack('<h', info[4:6])[0], int(info[7])])
    
    def register_callback(self, callback):
        self.extint = ExtInt(self.int_pin, ExtInt.IRQ_FALLING, Pin.PULL_UP, callback)

gt911 = GT911(I2C(1, freq = 100000), 'X12', 'X11')

def gt911_isr(_):
    # Get status register
    sta_reg = gt911.read_reg(0x814E, 1)[0]
    if sta_reg & 0x80 == 0:
        return
    # Get number of touch points
    npoints = sta_reg & 0xF
    # Display touch points
    print('\r', end = '')
    for id in range(npoints):
        info = gt911.get_touch_point(id + 1)
        print('(%4d, %3d) ' % (info[0], info[1]), end = '')
    # Fill blank to flush display
    for id in range(5 - npoints):
        print('            ', end = '')
    # Clear interrupt
    gt911.write_reg(0x814E, bytearray([0]))

print('Press USR button to stop')

# Attach ISR
gt911.register_callback(lambda e: schedule(gt911_isr, e))

while Switch().value() == False:
    pass

# Detach ISR
gt911.register_callback(None)