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116 | # Demo for Maker Pi RP2040 board
from machine import Pin,PWM
import time
import VL53L0X
buzzer=PWM(Pin(22))
sda=machine.Pin(0) # row one on our standard Pico breadboard
scl=machine.Pin(1) # row two on our standard Pico breadboard
i2c=machine.I2C(0, sda=sda, scl=scl, freq=400000)
# print("Device found at decimal", i2c.scan())
# The Maker Pi RP2040 has 13 fantastic blue GPIO status LEDs
blue_led_pins = [2, 3, 4, 5, 6, 7, 16, 17, 26, 27, 28]
# dist_scale = [2, 4, 6, 8, 10, 13, 16, 20, 25, 35, 50, 75, 100]
dist_scale = [2, 4, 6, 8, 10, 15, 20, 25, 50, 100, 150, 200, 300]
number_leds = len(blue_led_pins)
led_ports = []
delay = .05
# calibration parameters
zero_dist = 65 # distance measure when an object is about 1/2 cm away
max_dist = 350 # max distance we are able to read
scale_factor = .2
# create a list of the ports
for i in range(number_leds):
led_ports.append(machine.Pin(blue_led_pins[i], machine.Pin.OUT))
# Create a VL53L0X object
tof = VL53L0X.VL53L0X(i2c)
# blue up
for i in range(0, number_leds):
led_ports[i].high()
time.sleep(delay)
led_ports[i].low()
# blue down
for i in range(number_leds - 1, 0, -1):
led_ports[i].high()
time.sleep(delay)
led_ports[i].low()
# get the normalized time-of-flight distance
def get_distance():
global zero_dist, scale_factor
tof_distance = tof.read()
if tof_distance > max_dist:
return tof_distance
# if our current time-of-flight distance is lower than our zero distance then reset the zero distance
if tof_distance < zero_dist:
zero_dist = tof_distance
return int((tof_distance - zero_dist) * scale_factor)
def led_show_dist(in_distance):
global number_leds
for led_index in range(0, number_leds):
if in_distance > dist_scale[led_index]:
led_ports[led_index].high()
else:
led_ports[led_index].low()
def playtone(frequency):
buzzer.duty_u16(1000)
buzzer.freq(frequency)
def bequiet():
buzzer.duty_u16(0)
def play_no_signal():
playtone(100)
time.sleep(0.1)
bequiet()
def play_turn():
playtone(500)
time.sleep(0.1)
bequiet()
# start our time-of-flight sensor
tof.start()
valid_distance = 1
# loop forever
def main():
while True:
global valid_distance
distance = get_distance()
if distance > 1000:
# only print if we used to have a valid distance
if valid_distance == 1:
print('no signal')
valid_distance = 0
else:
print(distance)
if distance < 30:
play_turn()
valid_distance = 1
led_show_dist(distance)
time.sleep(0.05)
# clean up
# This allows us to stop the sound by doing a Stop or Control-C which is a keyboard intrrup
try:
main()
except KeyboardInterrupt:
print('Got ctrl-c')
finally:
# Optional cleanup code
print('turning off sound')
buzzer.duty_u16(0)
tof.stop()
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