This page has sections of code for doing things you might want in your programs. You may want to use them as procedures in your program. Make sure that they are put before any code that calls them.
This section of code will read the sensors on the wall sensor board. The global statements are defined so that you can access and display the lit and unlit values plus the resulting leftSensorValue, rightSensorValue, and frontSensorValue fields outside of the procedure. for use in your program or for diagnostic purposes
def readSensors(): # read wall sensors
#Values are derived by subtracting the lit value of a sensor
# from the unlit value
global leftSensorValue, rightSensorValue, frontSensorValue
global leftSensorLit, rightSensorLit, frontSensorLit
global leftSensorUnlit, rightSensorUnlit, frontSensorUnlit
global leftval, rightval, frontval
leftSensorUnlit = leftSensor.read_u16()
rightSensorUnlit = rightSensor.read_u16()
sidesEmitter.value(1)
time.sleep_us(75)
leftSensorLit = leftSensor.read_u16()
rightSensorLit = rightSensor.read_u16()
sidesEmitter.value(0)
frontSensorUnlit = frontSensor.read_u16()
frontEmitter.value(1)
time.sleep_us(75)
frontSensorLit = frontSensor.read_u16()
frontEmitter.value(0)
time.sleep_us(75)
leftSensorValue = (leftSensorLit - leftSensorUnlit) #
rightSensorValue = (rightSensorLit- rightSensorUnlit) #
frontSensorValue = (frontSensorLit- frontSensorUnlit)
This section of code will read the sensors on the line follower board
def readSensors(): # Read line and side marker sensors
global leftSensorValue, rightSensorValue
global radiusSensorValue, startSensorValue
global leftSensorUnlit, rightSensorUnlit
global radiusSensorUnlit, startSensorUnlit
emitter.value(0)
radiusEmitter.value(0)
leftSensorUnlit = leftSensor.read_u16()
rightSensorUnlit = rightSensor.read_u16()
startSensorUnlit = startSensor.read_u16()
radiusSensorUnlit = radiusSensor.read_u16()
emitter.value(1)
time.sleep_us(15)
leftSensorLit = leftSensor.read_u16()
rightSensorLit = rightSensor.read_u16()
startSensorLit = startSensor.read_u16()
emitter.value(0)
radiusEmitter.value(1)
time.sleep_us(15)
radiusSensorLit = radiusSensor.read_u16()
radiusEmitter.value(0)
leftSensorValue = (leftSensorUnlit - leftSensorLit)
rightSensorValue = (rightSensorUnlit - rightSensorLit)
startSensorValue = (startSensorUnlit - startSensorLit)
radiusSensorValue = (radiusSensorUnlit - radiusSensorLit)This section of code will repeatedly flash the LEDs on the mezzanine board and the three indicator LEDs on either sensor board. For the line sensor board it will also briefly flash the line and marker illumination LEDs
def flashLEDs():
i = 0
while True:
print ("flash LEDs", i)
i = i + 1
leftMezzLED.value(1) # left Mezzanine LED
rightMezzLED.value(1)
onBoardLED.value(1) # mini LED on Pico processor board
time.sleep(1)
leftMezzLED.value(0)
rightMezzLED.value(0) # right Mezzanine LED
onBoardLED.value(0)
time.sleep(1)
leftSensorLED.value(1) # Left LED on either sensor board
time.sleep(0.5)
centreSensorLED.value(1) # Centre LED on either sensor board
time.sleep(0.5)
rightSensorLED.value(1) # Right LED on either sensor board
time.sleep(1)
leftSensorLED.value(0)
centreSensorLED.value(0)
rightSensorLED.value(0)
emitter.value(1) # Line sensor line illumination LEDs
time.sleep(0.1)
emitter.value(0)
radiusEmitter.value(1) # Line sensor marker illumination LED
time.sleep(0.1)
radiusEmitter.value(0)