Getting code to my home assistant

[mserrar]

Hi I have an RF remote that works on 433Mhz. I tried to capture the code using my broadlink RM4, using broadlink app I can read the signal from the remote and replay it without a problem.
However I have an integration of my broadlink and home assistant. However after many failed attempt, I got to the point where I gave up on trying to capture the signal from home assistant using broadlink read RF function.

My solution right now and since RTL-SDR usb, the plan is to use it to capture the remote signal, encode it to base64 (this is what broadlink uses on home assistant to send RF signal) and then input the code manually on home assistant broadlink config.

I got to the point where I used SDR sharp with the RTL_33 plugin. I was able to listen and see the remote signal received.
However I have no idea how to get the signal raw data and convert it into base64. Any help will be much appreciated.
Thank you.

[zuckschwerdt]

The Broadlink base64 is just a way to display the binary data. You can encode and decode the data with e.g. https://base64.guru/converter/decode/hex

But we'll need to find out what those bytes in the Broadlink RF codes are make use of them. They should encode a OOK format in some way. https://triq.org/rtl_433/IQ_FORMATS.html#pulse-data-formats

It could be something like (according to https://github.com/mjg59/python-broadlink/blob/master/protocol.md)

• byte 0x00: Transmission type (0x26 = IR, 0xb2 for RF 433Mhz, 0xd7 for RF 315Mhz)
• byte 0x01: Repeat count (0 = no repeat, 1 send twice, .....)
• byte 0x02 - 0x03: Data length (little endian)
• byte 0x04...: Pulse data in pairs of (mark, space), lengths in 2^-15 s units (~30 µs)
  Each value is represented by one byte. If the length exceeds one byte then it is stored big endian with a leading 0.

We could add a conversion option to the Broadlink format for rtl_433's OOK files.

[zuckschwerdt]

Very good. That's a clean OOK signal. (It's 4 repeats of a PWM signal with preamble.)
It can be turned into a Broadlink code -- I'll post that converted Broadlink base64 later.

[mserrar]

Thank you, I really appreciate the help. Sorry for the noob questions, I am still in the learning phases.

[mserrar]

Here is something very interesting I found out after doing more tests.
I will try to make my scenarios as clear as possible.

Case 1:

I used rtl_433 to capture the signal from the remote. I was able to see the signal (this is what I sent you earlier)

Case 2:

I used broadlink app to trigger the learn function, I pressed the remote so that broadlink app was able to learn it.
After that I used only the broadlink app to replay the signal and I was able to trigger the command properly. So I assumed the signal is going from broadlink to my device I wanted to control.

Now I was curious to see what broadlink was sending as a signal, so I used rtl_433 again, but this time, instead of pressing the remote, I used the broadlink app, but I didn't see any signal captured by rtl_433, even if I can see that the device is being controlled.

I tried Universal Radio Hacker and I was able to capture the broadlink signal with it. So I noticed that with Universal radio hacker I am using HackRF One, when I switched it to use RTL-SDR , I wasn't able to capture the signal. (using rtl_433 , I was also using RTL-SDR)

So my conclusion is that RTL-SDR is not able to capture broadlink signal using rtl_433 or universal radio hacker. But it was able to capture the original remote signal. This makes me confused to be honest haha

I used hackrf one with rtl_433 and I was not able to capture signal from broadlink.

[zuckschwerdt]

Did you check if maybe the signal is at a different frequency and thus out of (the narrow) RTL-SDR band? The HackRF would have a wider band. Maybe try rtl_433 with -s 1024k

[zuckschwerdt]

The converted OOK data from the pdv link above should be sgNOACAgICAgICAgCBAIEBAICBAIEAgQEAgIEBAICBAIEBAICBAIEAgQEAgQCAgQEAgQCBAICBAQCBAIEAgQCAgQCBAIEBAICBAQCAgQAAAAAAAAAAAAAAAA
which is
b2 03 4e00 (433 MHz, 3 repeats, len 004e = 78) 2020 2020 2020 2020 (preamble) 0810 0810 1008 0810 0810 0810 1008 0810 1008 0810 0810 1008 0810 0810 0810 1008 1008 0810 1008 1008 1008 0810 1008 1008 1008 1008 0810 0810 0810 1008 0810 1008 0810 (bits 11011101 01101110 01000100 00111010 1) 000000 000000 000000 000000
not sure about the padding at the end though.