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furrtek / portapack-havoc

Custom firmware for the HackRF SDR + PortaPack H1 addon
GNU General Public License v2.0
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tip for epar/xylos #146

Open F0GPI opened 6 years ago

F0GPI commented 6 years ago

Hi, i have 3 cities around me on the same frequency who use bht for public lighting. Have you a tip for discover coding frames?

djecom1 commented 6 years ago

I use ScanScope as a CCIR decoder software for Xylos. For EPAR, I reverse the signal with a WAV viewer (audacity or..)

furrtek commented 6 years ago

You're off to decode the FSK EPAR frames by hand, you should only need the city code (8 bits). See http://furrtek.free.fr/?a=epar. For Xylos, you can also use Audacity with a spectrum view to match the tones to the symbols. The format is 0000CCFSRRBSSSSB0000 with CC=City code, F=Family, S=Subfamily, RR=Receiver ID, S=Relay states (0=Ignore, 1=Open, 2=Closed). Same consecutive symbols are coded with E (0000 becomes 0E0E) and A can be used as wildcard.

retalieight commented 6 years ago

Anyone know if Epar/Xylos (CCIR tones) are mainly only used in Europe? I'm trying to figure out what's used in the USA but I think it's just controlled by a sensor that detects daylight. :/

furrtek commented 6 years ago

I'm not aware of any city outside of France using Epar or Xylos. I know many cities use either light sensors or digital astronomical clocks (sometimes synced by GPS).

StoneSet commented 5 years ago

Hi, There are only 255 possibilities (so 8 bits), so you can try modifying the code of @furrtek project from 2012 (http://furrtek.free.fr/?a=epar). As soon as a command is sent, there are 255 possibilities tested and once the cities code is known you can directly inform the emitter without "brut force" the receiver, then, it will go faster to shutdown the area. I will try this technique myself, I come back to you as soon as I have results. Thanks