433 mhz - decoding receieved signal

Projects Networking, Protocols, and Devices
21

Hi jremington,
Thank you for your answer.

I have looked at the page, but I do not think that my output matches any of the examples shown.

I think right now the goal is to make the arduino succesfully toggle on the remote socket. When that happens, I know I am on the right track and can start decoding the other buttons to see if I can find any pattern (that is what protocols are about, right?).

So - do you have any comments on the previous post? Does my decoding look right? If yes, what is possibly going wrong since the remote is not toggled?

22

Given that the signal type is unknown, it is extremely unlikely that your decoding is correct.

It should work to replay the transmission as accurately as possible. The exception would be for a "rolling code" encrypted signal, which is designed to defeat replay efforts (common in garage door openers). In such a system, the signal for a given command is different every time it is sent.

23

Hi again,

I do not think it is a 'rolling code' - for two reasons. The signal is learned by the rf socket and the signal seems to be the same when the same button is pressed.

I think the first step would be to confirm that my decoding of the signal is correct as this is my first time doing this. Would anybody be willing to give it a shot if I upload the audacity file or a series of screenshots of the recorded signal?

24

Its unlikley to be a rolling code, but that doesnt make the task easier.
Can you dismantle the power point to see if there are any identifiable
chips inside.
Trying to decode an unknown protocol is almost impossible.
The other alternative is start looking for data encoders that have 14 pins, and then use the datasheets to analyse the protocol used.
Most manufacturers of RC power points dont make their own ICs and there arnt that many
data encoders on the market intended for driving OOK transmitters.
Have a look at this article

and see if this modified version of RC switch gets you better results.

25

Hi Mauried,

Thank you for your reply.
My first goal is not to decode the protocol, only to be able to sniff the signal and resend it (when you say 'decode the protocol' I understand that as trying to understand how the code is composed). Then, when I hopefully can do that succesfully, I will start trying to see if I can find any patterns in the codes.

I tried the modified version of rcswitch, but without succes.

I then tried to do some more analyzing of the signal that I can record with audacity through the line-in port of a computer. By doing that I think that there is something at the start of the signal that I am not getting correct. These are my findings so far, but I think that the part from 'start' to the first 'long pause' could be wrong. Maybe anybody would care to take a look at the audacity file and see if I am on the right track?

The file is attached.
The first track is when the button ON for chn A is hold down continiously.
The second track is when the button is pressed once. This is the track I've done the analysis on.

12,099297 12,099297 Start
12,099399 12,099399 1
12,100918 12,100918 0
12,102415 12,102415 0
12,103934 12,103934 1
12,105442 12,105442 1
12,106939 12,106939 0
12,108435 12,108435 1
12,109921 12,109921 1
12,111417 12,111417 0
12,112336 12,112336 0
12,112891 12,112891 long 1
12,117381 12,117381 0
12,118900 12,118900 1
12,120420 12,120420 0
12,121927 12,121927 1
12,123424 12,123424 0
12,124921 12,124921 0
12,126429 12,126429 1
12,127959 12,127959 1
12,129433 12,129433 0
12,130907 12,130907 0
12,132404 12,132404 0
12,133900 12,133900 0
12,135397 12,135397 0
12,135884 12,135884 long pause
12,138027 12,138027 1
12,139535 12,139535 0
12,141043 12,141043 0
12,142540 12,142540 1
12,144025 12,144025 1
12,145556 12,145556 0
12,147063 12,147063 1
12,148560 12,148560 1
12,150045 12,150045 0
12,151553 12,151553 1
12,153005 12,153005 1
12,154512 12,154512 0
12,156020 12,156020 0
12,157528 12,157528 1
12,159025 12,159025 0
12,160533 12,160533 1
12,162041 12,162041 0
12,163549 12,163549 0
12,165057 12,165057 0
12,166531 12,166531 1
12,168050 12,168050 0
12,169546 12,169546 0
12,171032 12,171032 0
12,172551 12,172551 0
12,174036 12,174036 0
12,174422 12,174422 long pause
12,176633 12,176633 1
12,178129 12,178129 0
12,179649 12,179649 0
12,181168 12,181168 1
12,182676 12,182676 1
12,184172 12,184172 0
12,185669 12,185669 1
12,187154 12,187154 1
12,188662 12,188662 0
12,190147 12,190147 1
12,191621 12,191621 1
12,193141 12,193141 0
12,194649 12,194649 0
12,196156 12,196156 1
12,197596 12,197596 0
12,199161 12,199161 1
12,200658 12,200658 0
12,202166 12,202166 0
12,203651 12,203651 1
12,205136 12,205136 1
12,206644 12,206644 0
12,208141 12,208141 0
12,209660 12,209660 0
12,211156 12,211156 0
12,212642 12,212642 0
12,213061 12,213061 long pause
12,215249 12,215249 1
12,216746 12,216746 0
12,218265 12,218265 0
12,219773 12,219773 1
12,221270 12,221270 1
12,222778 12,222778 0
12,224274 12,224274 1
12,225771 12,225771 1
12,227279 12,227279 0
12,228753 12,228753 1
12,230261 12,230261 1
12,231746 12,231746 0
12,233243 12,233243 0
12,234751 12,234751 1
12,236236 12,236236 0
12,237744 12,237744 1
12,239286 12,239286 0
12,240760 12,240760 0
12,242279 12,242279 1
12,243776 12,243776 1
12,245272 12,245272 0
12,246757 12,246757 0
12,248277 12,248277 0
12,249773 12,249773 0
12,251259 12,251259 0
12,251621 12,251621 long pause
12,253889 12,253889 1
12,255385 12,255385 0
12,256882 12,256882 0
12,258379 12,258379 1
12,259887 12,259887 1
12,261361 12,261361 0
12,262902 12,262902 1
12,264399 12,264399 1
12,265884 12,265884 0
12,267392 12,267392 1
12,268889 12,268889 1
12,270397 12,270397 0
12,271871 12,271871 0
12,273367 12,273367 1
12,274875 12,274875 0
12,276383 12,276383 1
12,277891 12,277891 0
12,279376 12,279376 0
12,280884 12,280884 1
12,282370 12,282370 1
12,283878 12,283878 0
12,285385 12,285385 0
12,286882 12,286882 0
12,288379 12,288379 0
12,289864 12,289864 0
12,290283 12,290283 long pause
12,292506 12,292506 1
12,293980 12,293980 0
12,295488 12,295488 0
12,296984 12,296984 1
12,298503 12,298503 1
12,300000 12,300000 0
12,301485 12,301485 1
12,302993 12,302993 1
12,304512 12,304512 0
12,305998 12,305998 1
12,307528 12,307528 1
12,309014 12,309014 0
12,310499 12,310499 0
12,312007 12,312007 1
12,313492 12,313492 0
12,314966 12,314966 1
12,316474 12,316474 0
12,317959 12,317959 0
12,319478 12,319478 1
12,320998 12,320998 1
12,322494 12,322494 0
12,323991 12,323991 0
12,325488 12,325488 0
12,326995 12,326995 0
12,328605 12,328605 0
13,146122 13,146122 end

Audacity file: Dropbox - NY.zip - Simplify your life