>MULTIPLE< AM2320 Sensors on one I2C line - connected to arduino - example??

Other Hardware Sensors
1

Dear Experienced Arduino Users!

I have a big question with the AM2320 type Digital Temperature and Humidity Sensor, manufactured by Aosong.
I have chosen this digital sensor device to measure humidity & heat with one compact device BECAUSE of it's I2C compatibility.
In the previous months I used 3 wire DHT sensors. These could not be placed on the same wire, every device needed an own dataline.
But now I got an exercise to solve, that more humidity sensors could be connected onto the same dataline.

So I started to search and found this device, as I mentioned : AM2320
It's datasheet tells that it has a standard I2C line. Also, as I looked into the datasheets, it mentions (on site 3 or 4, as I remember) bidirectional dataline... I'm not really in an intermediate level of the English language, but I thought, this also means the two-directional I2C communication, so I can change it's address, etc. to do what I mainly want.
Also, there was an image in that PDF sheet too, which showed a very simple image, about that multiple AM2320 sensor devices can be connected onto the same dataline - like the Dallas DS18B20 devices (but those are only heat-meters)

But I really could not find any example source code to use multiple of this devices. I looked onto it's public library too, here: AM2320/AM2320.h at master · thakshak/AM2320 · GitHub
And as I see, the address is fixed. :confused:
I have been thinking about that should it be used as in the case of the 16×4 character LCD panels? See: 4 LCD displays on 1 Arduino - hackmeister.dk
But there the address can be changed and the call of the initialization is different.

:frowning:

Could anyone help me int this case??
How can I - programatically - use multiple AM2320 Sensors connected to the same arduino, on the same SDA & SCL ports???

If it is not much to ask, an example code would be the best to understand! ::slight_smile:

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Learn https://learn.sparkfun.com/tutorials/i2c

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I have the same question and am wondering if there was a definitive answer.
I have added an arduino to control a chicken egg incubator, and want to have 3x temperature and humidity sensors so I can take the median temperature just in case a sensor fails I will still get accurate readings.

As text indicated i have also read that the address is fixed and that seems to be the case as I can swap AM2320 sensors without any reference to address in the code.

Otherwise I will have to buy some AM2302 and not use I2C

Comments / Suggestions?

Thanks
Thor

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It would be nice to use i2c but I just realized I can use the sensors I have with an analog input after re-reading the data sheet. At least I will not have to buy additional sensors.

Thor

5

Confused.
The AM2320 datasheet I am looking at tells me that this is a proprietary 1-wire bus sensor.
Not I2C, and not compatable with the Dallas 1-wire bus.
The sensor does not have an address.
You must be able to connect three sensors to three different Arduino pins, if there is a library for that sensor allows that.
Not sure what you mean with "analogue input". This is a digital sensor.
Leo..

6

Hi folks,

this is my first message at this forum. I have modified an existing AM2320 library https://github.com/Ten04031977/AM2320-master to be able to use multiple AM2320 sensors with the same Arduino. For achieve this I have used Software Wire library (I2C Software implementation).

You can check my little work at GitHub - lazyscheduler/AM2320: Arduino AM2320 Temperature and humidity sensor using software I2C

I hope this could help somebody