5V風(fēng)扇是筆記本拆下來(lái)的，接了個(gè)ss8550 NPNPNP三極管。

接線：

pi 5V --- 風(fēng)扇5V

風(fēng)扇GND --- 三接管C極

pi BCM 18 --- 三極管B極

pi GND --- 三極管E極

效果圖：

代碼：

#!/usr/bin/python3 # encoding: utf-8import RPi.GPIO import time RPi.GPIO.setwarnings(False) RPi.GPIO.setmode(RPi.GPIO.BCM) RPi.GPIO.setup(18, RPi.GPIO.OUT) pwm = RPi.GPIO.PWM(18, 75)duty = 0 lastDuty = 0try:while True:tmpFile = open('/sys/class/thermal/thermal_zone0/temp')temp = int(tmpFile.read())tmpFile.close()duty = 100;if temp >= 34500 :duty = 60if lastDuty >= 36500 :duty = 50if temp >= 38500:duty = 40if temp >= 40500:duty = 30if temp >= 42500:duty = 20if temp >= 44500:duty = 10if temp >= 46500:duty = 0if duty == 100:pwm.stop()time.sleep(0.2)RPi.GPIO.output(18, RPi.GPIO.HIGH)if duty == 0:pwm.stop()time.sleep(0.2)RPi.GPIO.output(18, RPi.GPIO.LOW)if duty > 0 and duty < 100:if lastDuty == 0 or lastDuty == 100:pwm.start(0)time.sleep(1)pwm.ChangeDutyCycle(duty)lastDuty = dutytime.sleep(5) except KeyboardInterrupt:pass pwm.stop() time.sleep(1) RPi.GPIO.output(18, RPi.GPIO.LOW)

總結(jié)

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