esp32 sending data to rtl_433 with ask protocol radiohead?

[Fred Freund]

Dear all,

I am using the rtl_433 for weatherstations , temp senors data to mqtt already.

Since this is working well I thought I could use the same setup to send my own data to it.

Is it possible to send data like 12 x  ds18b20 temp sensors to rtl_433 and decode it  with already existing decoders or do I need to define a decoder on my own . this would be still over my knowledge.

I thought of using an esp32 to 433 and ask from rediohead, but not shure how this can be done.

Any hint would be appreciated.

thank you

[Greg Troxel]

Fred Freund <freddd...@gmail.com> writes:

> I am using the rtl_433 for weatherstations , temp senors data to mqtt
> already.
> Since this is working well I thought I could use the same setup to send my
> own data to it.
>
> Is it possible to send data like 12 x ds18b20 temp sensors to rtl_433 and
> decode it with already existing decoders or do I need to define a decoder
> on my own . this would be still over my knowledge.

You should be able to get some kind of 433 MHz radio breakout board,
maybe RFM69, or CC1101. Then, you can write code to make your sensor
seem like an existing sensor, picking one that has a reliable checksum
method, like CRC.

Or you could design a protocol and also write a decoder.

> I thought of using an esp32 to 433 and ask from rediohead, but not shure
> how this can be done.

What I do is to use ESP8266 with "nodemcu" software, and write a small
bit of code that gets data from sensors and sends it over MQTT. That
does require running the wifi, which uses power, so if it's plugged in
that's fine, on battery not so much.

If you do want to run on batteries, you probably want a lower-power
microcontroller and to use the radio path above.

[Fred Freund]

Thank you,

I did this to a ventus 132 anemometer with a wemos d1 , then reversed since I get more data from other neighbor stations  too on rtl_433 and in MQTT this was shown as well like my dostmann rain sensor.

The second reason was the power supply of the nodemcus .(batteries are more handy)

Further I changed wlan password and had to change nodemcu sensors too and thought it would decrease vulnerability of my WLAN not having so many nodemcus wlan connected. (I assume)

I was the opinion the ask radiohead has just the transporting protcol/ setting and the data is free to define/choose but it seems it has to follow predefined data settings e.g.

house id , module id , etc.  which I found here rtl_433 ASK Radiohead

If I find a easy way to decode e.g. temp1  xxx C, temp2 xxx C usind rtl_433 I will post here

I am still on the search how to crc and where house id etc. comes from.

many Regards & thank you

[Greg Troxel]

Fred Freund <freddd...@gmail.com> writes:

> I did this to a ventus 132 anemometer with a wemos d1 , then reversed since
> I get more data from other neighbor stations too on rtl_433 and in MQTT
> this was shown as well like my dostmann rain sensor.

I don't follow that but that's ok.

> The second reason was the power supply of the nodemcus .(batteries are more
> handy)

To me this is the big reason.

> Further I changed wlan password and had to change nodemcu sensors too and
> thought it would decrease vulnerability of my WLAN not having so many
> nodemcus wlan connected. (I assume)

I don't think it hurts your LAN as long as no one steals the transmitter
and gets the key. You could run a second SSID and put it on a VLAN.
Really the big threat is having IOT type devices running proprietary
code (smart speakers, cameras, printers, thermostats, garage door
controllers) and it only makes sense to worry about your own ESP things
once you have banished all those.


GOod luck and keep us posted.