SunFounder ESP32

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SunFounder ESP32 Starter Kit

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# Initialize the LCD1602 display

lcd = LCD()

dis = 100

# Calculate the distance

def distance():

# Ensure trigger is off initially

TRIG.off()

time.sleep_us(2) # Wait for 2 microseconds

# Send a 10-microsecond pulse to the trigger pin

TRIG.on()

time.sleep_us(10)

TRIG.off()

# Wait for the echo pin to go high

while not ECHO.value():

pass

# Record the time when the echo pin goes high

time1 = time.ticks_us()

# Wait for the echo pin to go low

while ECHO.value():

pass

# Record the time when the echo pin goes low

time2 = time.ticks_us()

# Calculate the time difference between the two recorded times

during = time.ticks_diff(time2, time1)

# Calculate and return the distance (in cm) using the speed of sound (340 m/s)

return during * 340 / 2 / 10000

# Thread to continuously update the ultrasonic sensor reading

def ultrasonic_thread():

global dis

while True:

dis = distance()

# Clear the LCD screen

lcd.clear()

# Display the distance

lcd.write(0, 0, 'Dis: %.2f cm' % dis)

time.sleep(0.5)

# Start the ultrasonic sensor reading thread

_thread.start_new_thread(ultrasonic_thread, ())

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422 Chapter 3. For MicroPython User