IR reversing protocol with pickit2

[darthblade11]

Hi there everyone,
okay so first off, don't really know if this is the right section to put this post in but anyway, here goes.

Right so what I have been attempting to do is reverse engineer the protocol for a pioneer remote (xxd3058).
What i have managed to do so far is get carrier frequency, 40kHz, and two packets of data, both of them being the same data the on/off command.

images attached,
2 packet
carrier

So, from here how do i start seeing what is what? I mean How do i find the structure of the packet?

Thanks for the help in advance.

 

[hexreader]

A bit of Googling suggests to me that Pioneer is much the same thing as NEC2 protocol, but using 40kHz carrier instead of 38kHz.

The packet image that you posted looks nothing like NEC protocol and nothing like any other protocol that I have ever seen.

I suspect that you may have a problem with the hardware that you are using, and that you are not receiving an accurate signal.

A 3-pin IR receiver chip (even a 38kHz one) should demodulate the signal fairly accurately (but gives an upside-down signal).

My favourite site for explaining IR remote protocols is here: https://www.sbprojects.com/knowledge/ir/nec.php

Be sure to read about extended NEC protocol

 

[darthblade11]

Thank you for your prompt reply,
Will look further into the hardware and protocol.
Wanted to go that way, but don't have an IR receiver chip lying around, since I live far it is somewhat difficult for me to acquire.

How i am getting the signal is by connecting directly to the CARR pin of a microcontroller (M34570M8-XXXFP) with the pickit2 logic analyzer tool.

Perhaps this is not the best method to read the signal? Perhaps some interference or maybe the schmidt trigger in the logic tool has some false readings because the remote runs on 3v?

In any case, thank you kindly for your help.

 

[hexreader]

Find an old Sony video recorder in the nearest skip, and take the 3-pin IR receiver chip out of it. Before you do, chase the 0V, +5V and signal wires to check on the receiver pin-out.

Wire the 3-pin receiver 0v, +5V and data pins directly to your PICkit2 and tell the PK2 to supply power.

Other brands of Video recorder, DVD etc will do too, but would be 38kHz 3-pin receiver, which will work just as well, but range will be halved.