Intergrate MQ135 sensor with ttn-abp-feather-us915-dht22

[alifj98]

Hey guys, im fairly new in this. But i managed to upload ttn-abp-feather-us915-dht22 and my dht22 sensor is sending the needed data to TTN.

I am trying to add another sensor (MQ135) as i need to read the air quality info. Any idea how to integrate the sensor in the same code as well as the payload decode to for TTN to read the data?

I appreciate any help anyone can give, thank you.

Lora sensor node: Dragino Lora GPS Shield with Arduino mega
Gateway: Dragino LG308

[terrillmoore]

Hi @alifj98 -- you could look at some of MCCI's sketches -- like the scd30_lorawan example in the MCCI_Catena_SCD30 library. If you look in extras, you'll find the decoder and a markdown description. When I'm designing a protocol, I always start by describing it, and then writing the test vectors and the simple test generation program.

Then I can go to the TTN or Helium, console, set up an app, load the javascript, drop in the test data and get json results.

There is no need to be as complicated as we are in building the data -- I'm afraid that's due to various bad experiences in previous lives, and an attempt to build a product rather than an experiment. The key thing is to add some kind of tag to identify your data to the decoder, so that if you change, the decoder will at least recognize that it doesn't understand (rather than making up bad answers). Also, transmitting data in binary rather than ASCII is usually better: shorter messages save power and are good for the network. (If you can fit in 11 bytes, you can work even at the slowest rate in the US.) I have been meaning to rewrite the encoding library in a more structured way, because it is generally useful; but no time.

Best regards,
--Terry