RGB LED颜色控制
- #!/usr/bin/env python
-
- import RPi.GPIO as GPIO
- import time
-
- colors = [0xFF0000, 0x00FF00, 0x0000FF, 0xFFFF00, 0xFF00FF, 0x00FFFF, 0xFFFFFF, 0x9400D3]
- pins = {'pin_R':11, 'pin_G':12, 'pin_B':13} # pins is a dict
-
- GPIO.setmode(GPIO.BOARD) # Numbers GPIOs by physical location
- for i in pins:
- GPIO.setup(pins[i], GPIO.OUT) # Set pins' mode is output
- GPIO.output(pins[i], GPIO.HIGH) # Set pins to high(+3.3V) to off led
-
- p_R = GPIO.PWM(pins['pin_R'], 2000) # set Frequece to 2KHz
- p_G = GPIO.PWM(pins['pin_G'], 2000)
- p_B = GPIO.PWM(pins['pin_B'], 5000)
-
- p_R.start(100) # Initial duty Cycle = 100(leds off)
- p_G.start(100)
- p_B.start(100)
-
- def map(x, in_min, in_max, out_min, out_max): # 将一个数从一个区间线性映射到另一个区间，比如将0~100之间的一个数映射到0~255之间
- return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min
-
- def setColor(col): # For example : col = 0x112233
- R_val = (col & 0xFF0000) >> 16
- G_val = (col & 0x00FF00) >> 8
- B_val = (col & 0x0000FF) >> 0
-
- R_val = map(R_val, 0, 255, 0, 100) # change a num(0~255) to 0~100.
- G_val = map(G_val, 0, 255, 0, 100)
- B_val = map(B_val, 0, 255, 0, 100)
-
- p_R.ChangeDutyCycle(100 - R_val) # Change duty cycle
- p_G.ChangeDutyCycle(100 - G_val)
- p_B.ChangeDutyCycle(100 - B_val)
-
- try:
- while True:
- for col in colors:
- setColor(col)
- time.sleep(0.5)
- except KeyboardInterrupt:
- p_R.stop()
- p_G.stop()
- p_B.stop()
- for i in pins:
- GPIO.output(pins[i], GPIO.HIGH) # Turn off all leds
- GPIO.cleanup()
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