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| 1 | +from machine import Pin # Allows us to use "Pin" to use code to interface with the pins on our board |
| 2 | + |
| 3 | +from machine import ADC # Allows us to use "ADC" (analog-to-digital conversion) to read from our analog pin |
| 4 | + |
| 5 | +from machine import PWM # Allows us to use "PWM" (pulse-width modulation) to control the brightness of our LED |
| 6 | + |
| 7 | +import time # Import the time module to use sleep for delays |
| 8 | + |
| 9 | +pwmBlue = PWM(Pin(32), freq=1000, duty_u16=0) # Create a PWM object on pin 28 with a frequency of 1000Hz and an initial "on time" of 0 (off) |
| 10 | +pwmGreen = PWM(Pin(30), freq=1000, duty_u16=0) # Create a PWM object on pin 27 with a frequency of 1000Hz and an initial "on time" of 0 (off) |
| 11 | +pwmRed = PWM(Pin(28), freq=1000, duty_u16=0) # Create a PWM object on pin 26 with a frequency of 1000Hz and an initial "on time" of 0 (off) |
| 12 | + |
| 13 | +# Let's create functions for various colors that we can call later |
| 14 | + |
| 15 | +# Since our PWM "on time" or duty cycle is 16 bits, it is a value between 0 and 65535. |
| 16 | +# It's useful to store a variable for maximum brightness so we can use percentages of it easily. |
| 17 | +kMaximumBrightness = 65535 # Maximum brightness value for PWM |
| 18 | + |
| 19 | +# These are "functions" that we can "call" to set the color of the LED. |
| 20 | +# Notice the "def" keyword, which is used to define a function in Python. |
| 21 | +# Now, we can call these later by just typing their names like `red()`, `green()`, etc. |
| 22 | +# And all the code inside the function will run. |
| 23 | + |
| 24 | +def red(): |
| 25 | + # The "duty_u16" method sets the duty cycle or "on time" for the PWM pin. |
| 26 | + pwmRed.duty_u16(kMaximumBrightness) # Set the red LED to full brightness |
| 27 | + pwmGreen.duty_u16(0) # Turn off the green LED |
| 28 | + pwmBlue.duty_u16(0) # Turn off the blue LED |
| 29 | + |
| 30 | +def orange(): |
| 31 | + pwmRed.duty_u16(kMaximumBrightness) # Set the red LED to full brightness |
| 32 | + pwmGreen.duty_u16(int(kMaximumBrightness * 0.25)) # Set the green LED to quarter brightness (by multiplying by 0.5) |
| 33 | + pwmBlue.duty_u16(0) # Turn off the blue LED |
| 34 | + |
| 35 | +def yellow(): |
| 36 | + pwmRed.duty_u16(kMaximumBrightness) # Set the red LED to full brightness |
| 37 | + pwmGreen.duty_u16(kMaximumBrightness) # Set the green LED to full brightness |
| 38 | + pwmBlue.duty_u16(0) # Turn off the blue LED |
| 39 | + |
| 40 | +def green(): |
| 41 | + pwmRed.duty_u16(0) # Turn off the red LED |
| 42 | + pwmGreen.duty_u16(kMaximumBrightness) # Set the green LED to full brightness |
| 43 | + pwmBlue.duty_u16(0) # Turn off the blue LED |
| 44 | + |
| 45 | +def cyan(): |
| 46 | + pwmRed.duty_u16(0) # Turn off the red LED |
| 47 | + pwmGreen.duty_u16(kMaximumBrightness) # Set the green LED to full brightness |
| 48 | + pwmBlue.duty_u16(kMaximumBrightness) # Set the blue LED to full brightness |
| 49 | + |
| 50 | +def blue(): |
| 51 | + pwmRed.duty_u16(0) # Turn off the red LED |
| 52 | + pwmGreen.duty_u16(0) # Turn off the green LED |
| 53 | + pwmBlue.duty_u16(kMaximumBrightness) # Set the blue LED to full brightness |
| 54 | + |
| 55 | +def magenta(): |
| 56 | + pwmRed.duty_u16(kMaximumBrightness) # Set the red LED to full brightness |
| 57 | + pwmGreen.duty_u16(0) # Turn off the green LED |
| 58 | + pwmBlue.duty_u16(kMaximumBrightness) # Set the blue LED to full brightness |
| 59 | + |
| 60 | +def turnOff(): |
| 61 | + pwmRed.duty_u16(0) # Turn off the red LED |
| 62 | + pwmGreen.duty_u16(0) # Turn off the green LED |
| 63 | + pwmBlue.duty_u16(0) # Turn off the blue LED |
| 64 | + |
| 65 | + |
| 66 | +# Remember, we've already defined our RGB pins and functions above. |
| 67 | +# Make sure you have run the cells above this one first!!! |
| 68 | +photoresistor = ADC(Pin.board.A0) # Create an ADC variable for reading the photoresistor value from analog pin A0 |
| 69 | +potentiometer = ADC(Pin.board.A1) # Create an ADC variable for reading the potentiometer value from analog pin A1 |
| 70 | + |
| 71 | +# We'll set our photo-resistor threshold to a quarter of the maximum value of the ADC reading (65535) |
| 72 | +threshold = 65535 / 4 |
| 73 | +potentiometerMax = 65535 # Maximum value for the potentiometer reading |
| 74 | + |
| 75 | +# Infinite loop to continously read the photoresistor and potentiometer values |
| 76 | +while True: |
| 77 | + photoValue = photoresistor.read_u16() # Read the photoresistor value (0 to 65535) |
| 78 | + potPosition = potentiometer.read_u16() # Read the potentiometer value (0 to 65535) |
| 79 | + # Print the values to the console |
| 80 | + print(f"Photoresistor Value: {photoValue: 5}, Potentiometer Value: {potPosition : 5}", end='\r') # Print our readings (don't mind the fanciness of this line it just makes the print format nicely) |
| 81 | + |
| 82 | + # Check if the photoresistor value is below the threshold |
| 83 | + if photoValue < threshold: |
| 84 | + # If the photoresistor value is below the threshold, set the LED color based on the potentiometer position |
| 85 | + # Let's split the range 0 - 65535 into 7 equal(ish) parts for different colors |
| 86 | + if potPosition > 0 and potPosition < 9362: |
| 87 | + red() |
| 88 | + if potPosition >= 9362 and potPosition < 18725: |
| 89 | + orange() |
| 90 | + if potPosition >= 18725 and potPosition < 28087: |
| 91 | + yellow() |
| 92 | + if potPosition >= 28087 and potPosition < 37450: |
| 93 | + green() |
| 94 | + if potPosition >= 37450 and potPosition < 46812: |
| 95 | + cyan() |
| 96 | + if potPosition >= 46812 and potPosition < 56175: |
| 97 | + blue() |
| 98 | + if potPosition >= 56175 and potPosition <= 65535: |
| 99 | + magenta() |
| 100 | + |
| 101 | + else: # Note that this "else" aligns with the photovalue < Threshold condition above. |
| 102 | + turnOff() # Turn off the LED if the photoresistor value is above the threshold |
| 103 | + |
| 104 | + time.sleep(0.250) # Sleep for 0.25 seconds to avoid flooding the console with prints |
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