1. # -*- coding:utf-8 -*-
    3. """
    4. 根据CPU温度开启与关闭树莓派风扇
    5. """
    7. import time, os
    8. import RPi.GPIO as GPIO
    9. import logging
    11. GPIO_OUT = 14
    12. START_TEMP = 55
    13. CLOSE_TEMP = 45
    14. DELAY_TIME = 15
    15. LOG_PATH = '/var/log/fan_control.log'
    17. logging.basicConfig(level=logging.DEBUG,
    18.                     format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',  # 日志格式
    19.                     datefmt='%Y-%m-%d %H:%M:%S',  # 时间格式
    20.                     filename=LOG_PATH,  # 日志的输出路径
    21.                     filemode='a')  # 追加模式
    23. def get_cpu_temperature():
    24.     """
    25.     获取树莓派CPU温度, 读取/sys/class/thermal/thermal_zone0/temp内容, 除1000就是温度
    26.     :return: float
    27.     """
    28.     with open("/sys/class/thermal/thermal_zone0/temp", 'r') as f:
    29.         temperature = float(f.read()) / 1000
    30.     return temperature
    33. def start_fan(temp):
    34.     """
    35.     开启风扇
    36.     :param temp: 树莓派CPU温度
    37.     :return:
    38.     """
    39.     logging.info('power on fan, temp is %s' % temp)
    40.     # PNP型三极管基极施加低电平时才导通电路, NPN型三极管相反
    41.     GPIO.output(GPIO_OUT, GPIO.LOW)
    44. def stop_fan(temp):
    45.     """
    46.     关闭风扇
    47.     :param temp: 树莓派CPU温度
    48.     :return:
    49.     """
    50.     logging.info('power off fan, temp is %s' % temp)
    51.     # 基级施加高电平
    52.     GPIO.output(GPIO_OUT, GPIO.HIGH)
    55. def setup_GPIO():
    56.     """
    57.     GPIO初始化
    58.     风扇设置为关闭状态
    59.     :return:
    60.     """
    61.     GPIO.setmode(GPIO.BCM)
    62.     GPIO.setwarnings(False)
    63.     GPIO.setup(GPIO_OUT, GPIO.OUT, initial=GPIO.HIGH)
    66. def control_fan():
    67.     is_closed = True
    68.     try:
    69.         while True:
    70.             temp = get_cpu_temperature()
    71.             logging.debug("temperature: %s" % temp)
    72.             # 温度大于START_TEMP开启风扇， 低于CLOSE_TEMP关闭风扇
    73.             if (temp > START_TEMP and is_closed):
    74.                 start_fan(temp)
    75.                 is_closed = False
    76.             elif (temp < CLOSE_TEMP and not is_closed):
    77.                 stop_fan(temp)
    78.                 is_closed = True
    79.             else:
    80.                 pass
    81.             time.sleep(DELAY_TIME)
    82.     except Exception as e:
    83.         GPIO.cleanup()
    84.         logging.error(e)
    86. if __name__ == '__main__':
    87.     os.environ["TZ"] = 'Asia/Shanghai'
    88.     time.tzset()
    89.     logging.info('started control fan...')
    90.     setup_GPIO()
    91.     control_fan()
    92.     logging.info('quit started control fan...')