hcsr04Test.py

   1 from machine import Pin, time_pulse_us, I2C
   2 import time
   3 from lcd_api import LcdApi
   4 from pico_i2c_lcd import I2cLcd
   5
   6 # Define LCD I2C pins/BUS/address
   7 SDA = 2
   8 SCL = 3
   9 I2C_BUS = 1
  10 LCD_ADDR = 0x27
  11
  12 msg=0
  13 # Define LCD rows/columns
  14 LCD_NUM_ROWS = 2
  15 LCD_NUM_COLS = 16
  16
  17 # Set up LCD I2C
  18 lcdi2c = I2C(I2C_BUS, sda=machine.Pin(SDA), scl=machine.Pin(SCL), freq=400000)
  19 lcd = I2cLcd(lcdi2c, LCD_ADDR, LCD_NUM_ROWS, LCD_NUM_COLS)
  20
  21 def lcdPrint(msg):
  22     lcd.putstr(str(msg))
  23
  24 SOUND_SPEED=340
  25 TRIG_PULSE_DURATION=10
  26
  27 trig_pin=Pin(1, Pin.OUT)
  28 echo_pin=Pin(0,Pin.IN)
  29
  30 while True:
  31     trig_pin.value(0)
  32     time.sleep_us(5)
  33     trig_pin.value(1)
  34     time.sleep_us(TRIG_PULSE_DURATION)
  35     trig_pin.value(0)
  36
  37     ultransonic_duration=time_pulse_us(echo_pin,1,30000)
  38     distance_cm=SOUND_SPEED*ultransonic_duration/20000
  39
  40     print(f"Distance: {distance_cm} cm")
  41     msg=(f"{distance_cm} cm")
  42     lcdPrint(msg)
  43     time.sleep_ms(500)
  44     lcd.clear()
  45
  46
  47