Add support for Elko Wireless

[ubernoob]

Hi!

ELKO (elko.no) is the largest manufacturer of electrical products in Norway. Unfortunately they don't have any good system for controlling it from a computer or a mobile. So I would like to try to add support for Elko wireless in FHEM.

I know they use:
Frequency 868 MHz
GFSK modulation
Data rate 2,4 kbps

I have bought a CUL v3.2 device from busware.de Uploaded firmware to the device from http://culfw.de/culfw.html
I have also installed FHEM on a Raspberry Pi, so I should be all set to go.

But now I'm stuck. I need to set the device to listen to 868Mhz, and try to reverse engineer the protocol or try to record and duplicate the signals so I can control my lights from the machine.

Any suggestions where to go from here?

[ubernoob]

Would it help if you could get ssh access to the raspberry pi?

[rudolfkoenig]

Hi ubernoob.

Warning: this is most probably hard work, and it is possible that the CUL is not able to decode the signals correctly.

If you still want to try:

- try to find a CC11xx parameter configuration for the protocol on the web. Since there are no obvious OpenSource projects, I think you wont find any.
Gathering as much information as possible will help you for the next tasks.

- Read the CC1101.pdf from TI, and try out the freely available Windows SmartRF-Studio software.

- Configure the CC1101 like SlowRF in culfw does, but with 2.4kHz datarate and GFSK, so your code will receive an interrupt for each signal-level-change

- If this works, then you'll get an "edge-stream". Create a log for some telegrams, and figure out how a bit is coded, how many preambel and sync-bits there are, what is the parity/checksum.

- If this is understood, and you're lucky (and know the CC1101 configuration well), then configure the CC1101 to packet mode, so you'll get readily analyzed bytes from the CC1101.

- Probably you wont be lucky, and have to analyze the bits in C-Code, like it is done in the SlowRF part of culfw for FS20/EM/TX/etc. 2.4 kHz should be manageable for the 8MHz CUL.

In the meantime I would try some social engineering with Elko :)

Regards,
  Rudi