Question

I am trying to use Raspberry Pi 2 to connect two sensors and let them work. They are a DFROBOT analog light sensor and a DFROBOT analog sound sensor.

I am also using a AD converter, and the converter connect to SCL and SDA pins on Raspberry Pi.

The converter has four Ains, so I can use two of them, one connect to light sensor, one connect to sound sensor.

Could somebody help me with the Python code? I want to let my Pi receive 1 second for Ain1(Light sensor) and 1 second for Ain2(Sound sensor), alternately.

Here is my code, but It seems that it doesn't work well.

import time

import datetime

from smbus import SMBus

bus = SMBus(1)

def readSoundSensor():

    return bus.read_byte(0x48)

def runSoundSensor():

    bus.write_byte(0x48,0x00)
    last_reading = -1
    sound = readSoundSensor()
    timestamp= datetime.datetime.utcnow()
    record = str(timestamp) + ":" +str(sound)
    print "Sound: "+record

def readLightSensor():

    return bus.read_byte(0x48)

def runLightSensor():

    bus.write_byte(0x48,0x01)
    last_reading = -1
    light = readLightSensor()
    timestamp= datetime.datetime.utcnow()
    record = str(timestamp) + ":" +str(light)
    print "Light: "+record

while(Ture):

   runSoundSensor()

   time.sleep(1)

   runLightSensor()

   time.sleep(1)

My Pi has some data, but I data is not what I want, and is not as when I connect just a single sound/light sensor.

I am totally new in Raspberry Pi, and I don't know anything about address 0x48, etc, I just learn from some guide. Could someone help me where I was wrong?

Answer 1

您的while(Ture):显然是错误的。

您正在为两个传感器的A / D写相同的命令 - 0x48 0x00 - 这是不正确的，除非它在每次读取时对所有输入进行采样？

您确定拥有正确的SMBUS地址 - 0x48吗？这个命令0x00的意图是什么？

为了澄清，SMBUS命令将由address in hex, command byte(s) in hex组成。您可能想要了解SMBUS / I2C寻址：This文章非常好。

我认为至少你需要发送一个命令来选择一个Ain输入，然后另一个输入来对其进行采样。 0x00看起来更像是重置。

您是否阅读过A / D的文档？

How to connect two sensors into Raspberry Pi?

1 个答案: