no issue. just question of CC1101 use

[wazoo-pixel]

Hi.
Is it possible to “emulate” Oregon Scientific 433 MHz wireless sensors?
I have a small old SL103 touch weather station, but the outdoor sensors have stopped working over the years (SL109H) and these sensors are obsolete and very expensive second-hand.
That's why I'm looking to “emulate” these external sensors with an ESP32 + CC1101, so I can reuse the base station, forwarding HA or ESPhome temp/humid sensors.

ThankU

[juanboro]

Yes --- definitely possible - and likely somewhat easy as there is alot of information out there available on these. The approach I'd recommend is to add remote transmitter support for the devices in question to esphome. A simple example I did for my ceiling fans is here: esphome/esphome@dev...juanboro:esphome:remote_sofucor_fan (see files changed tab). It's not too difficult to add more protocols to the esphome remotes by just following their existing code patterns for other remote protocols. For the encoding of the Oregon Scientific devices - luckily these are already all coded up in rtl_433 --- see: https://github.com/merbanan/rtl_433/blob/master/src/devices/oregon_scientific.c --- the most important part is at the bottom where they define the device:

r_device const oregon_scientific = {
        .name        = "Oregon Scientific Weather Sensor",
        .modulation  = OOK_PULSE_MANCHESTER_ZEROBIT,
        .short_width = 440, // Nominal 1024Hz (488us), but pulses are shorter than pauses
        .long_width  = 0,   // not used
        .reset_limit = 2400,
        .decode_fn   = &oregon_scientific_decode,
        .fields      = output_fields,
};

You mainly need to implement decode/encode of that message. The OOK_PULSE_MANCHESTER_ZEROBIT modulation might be a little tricky just because my recollection is the one example in the esphome code of that modulation I believe is still broken --- I need to follow up with them on this PR: esphome/esphome#7532 -- but I believe my updated RC5 decoder properly implements demodulating that (and the transmit Manchester encoding modulation example is correct).

If you don't want to go the route of extending the remote receive/transmit - you can also do something similar by creating a custom component --- that is the route @swoboda1337 went with the acurite decoders here: https://github.com/swoboda1337/acurite-esphome .

There are many other possibilities as well --- since it's pretty straight forward to get the raw data received/transmitted in and out of esphome --- you can send it off to other areas to process it with python, etc - whatever is easiest. When I was playing with some of this in the past -- I ended up writing a girs custom component: https://github.com/juanboro/esphome/tree/mymaster/juanboro/girs --- which allows receiving and transmitting signals via https://github.com/bengtmartensson/IrScrutinizer -- while it says it is for IR -- it works great with RF stuff like this as well. For the ceiling fans -- once I reverse engineered the decoding/encoding in python/jupyter - then I implemented the remote code in C.

[swoboda1337]

Remote transmitter is easy to call from a component or from a lambda. Here is an example component: https://github.com/swoboda1337/somfy-esphome/blob/main/components/somfy/somfy.cpp#L31

Lambda example:

      auto call = id(my_transmitter).transmit();
      esphome::remote_base::RawTimings timings = {+601, -613, +601, -613, +601, -613, +601, -613};
      timings.push_back(+405);
      timings.push_back(-209);
      call.get_data()->set_data(timings);
      call.set_send_times(3);
      call.set_send_wait(2000);
      call.perform();

[wazoo-pixel]

wow
thankU so much @juanboro @swoboda1337
I will take a look to your instructions.