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Topic: Deciphering an unknown serial feed (Read 1 time) previous topic - next topic

Magician

O'K than, so it's not RF power, this all about AC electrical power.
In my previous post I give universal algorithm.
If you deal with AC,, so change AC power level (current or load).
The idea to solve the puzzle, "black box - device"  is:
change input (RF, AC, water, gaz etc) and look at the output.
You have to find a pattern.
No pattern, looks mess before and after - bit-rate is wrong.

scruss


No pattern, looks mess before and after - bit-rate is wrong.

And that's pretty much what I have to do. Thanks to all!

westfw

It is probably easiest to start out assuming certain data formats (async, 1200bps, 8databits 1 startbit one stopbit) and see if it fits.  Then try inverted async.  Don't forget that this is a cheap consumer product that probably contains a standard microprocessor of some kind, and it probably uses a data format supported by that micro, which is probably an async uart (I2C and SPI being fundamentally more-than-one-wire protocols.)

Can you take apart the existing receiver (or transmitter, except that would be more dangerous) and see what's there?  It may have a little 433MHz module just like we use, in which case you can look at where it's being fed from/to.

You can use your arduino as a sort of one-wire logic analyzer for things like this.  Sample the incoming bitstream from the receiver module every 10 microseconds or so for the entire duration of the transmission, store the results in RAM and dump to a PC for display and interpretation.  Or measure intervals between changes and send those...

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