树莓派4b测量PM2.5

1.GP2Y1010AU0F粉尘传感器连接图 

2. GP2Y1010AU0F工作原理

工作原理

传感器中心有个洞可以让空气自由流过，定向发射LED光，通过检测经过空气中灰尘折射过后的光线来判断灰尘的含量。 

3.源代码

main.py

# coding=UTF-8
import RPi.GPIO as GPIO
from ADC import ADS1015
from ADC import ADS_POINTER_CONFIG
import time
import math
import smbus
# import serial
COV_RATIO = 0.2  # //ug/mmm / mv
NO_DUST_VOLTAGE = 400  # //mv
SYS_VOLTAGE = 5000
density = 0.0
voltage = 0.0
# int adcvalue=0
def SendVideo():
    ads1015 = ADS1015()
    state = ads1015._read_u16(ADS_POINTER_CONFIG) & 0x8000  # 气体传感器连接确立
    if (state != 0x8000):
        print("\nADS1015 Error\n")
        # 收集气体数据
    GPIO.setmode(GPIO.BOARD)
    IN1 = 16
    GPIO.setwarnings(False)
    GPIO.setup(IN1, GPIO.OUT)  # 初始化二极管灯
    GPIO.output(IN1, GPIO.LOW)  # 关闭二级管灯
    # ser = serial.Serial("/dev/ttyAMA0",9600)
    # def Filter(m):
    while 1:
        GPIO.output(IN1, GPIO.HIGH)  # 启动二极管灯
        # AIN2_DATA=ads1015.ADS1015_SINGLE_READ(2)
        time.sleep(0.00028)  # 等待0.28ms
        AIN2_DATA = ads1015.ADS1015_SINGLE_READ(2)
        # AIN0_DATA=((AIN0_DATA*2-64)/2000.00+0.02)*2
        time.sleep(0.00004)  # 持续采集0.04ms
        GPIO.output(IN1, GPIO.LOW)  # 关闭二级管灯
        time.sleep(0.00986)
        voltage = (5000 / 1024.0) * AIN2_DATA * 1.1 * 2  # 计算气体浓度
        if (voltage >= NO_DUST_VOLTAGE):
            voltage -=