IRForum

Hello,

I'm desperately trying to decode a York A/C remote. I had some success by using your software. The remote is decoded as ELECTROLUX96_192AC.

I can see that the remote is sending 2x6 bytes, where the second 6 bytes are inverse of the first 6. So far so good.

I've also been able to find what each byte means (mode select, temperature, fan etc..), see attached PDF file.

What is bothering me is the checksum byte (Byte 6). I tried everything and I cannot find what algorithm is used for calculation. Can I please ask you to just briefly glance over the remote code and see if it looks obvious to you?

@joker_mkd

Thanks for posting the field descriptions & session file.

I will have a look and come back shortly...

Select LSB8 format from the powertools menu & decode all signals again
Using the checksum calculator under Power tools menu.

Set to ignore last byte

checked a few signals and they come up as XOR

If you XOR every BYTE you get 00

to generate the checksum, XOR all bytes except the last one and place in the last position.

Because the signal is in 2 bursts (48 bits + 48 bits), it is likely that there is an XOR at the end of the first burst as well - so you would calculate the XOR for each burst.

Using the reverse engineering tool (under Power Tools menu)shows that there is most likely 2 checksums.


You should review out Youtube videos for AC reverse engineering & checksum calculator.
https://www.youtube.com/AnalysIR/videos

Thanks for the insights. It helped me focus. I actually have a Senville AURA heat pump and it is close but slightly different.

It's message is 48 bits, repeated where the repeated message has its bits reversed.

40 bits are the data, 8 bits are the checksum. The checksum is first byte by byte reversed MSB/LSB, then summed in an 8 bit register, and then one subtracted before the result is reversed again.

Almost the same but slightly different.

code is at : https://github.com/kpishere/IRDecoder

@kphere...thanks for posting the info