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IR code?

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hmmpic:
Hello

I working on a IR remote for a Panasonic heat pump. But I cant find any information on the IR.

I have make some measurement on the IR code and here are the logic dump.

What I found is:
When looking at the smallest pulse it is: 435us, this mean that it start with:
8 Low (pulses) - 3 High (pulses)
From Trigger to marker B is always the same!! It start with 8L then 3H
From Marker B to D is the one there change. It start with 8L then 3H

Is there some help?

hmmpic:
Hi

The 8L and 3H is equal to 8*435=3,4ms / 3*435=1,3ms.
The starting point is at Trigger then you see L for 3,4ms and then H for 1,3ms.
After it the code came. Then you see a long H=(about)10ms. Then the real part start with the same 8L=3,4ms and 3H=1,3ms.
A L is 1*435.
A H is 2*435.

All above is just my best guess.

hmmpic:
Hi

The problem is not to decode this dump, but figure out how the code is build up:-) I can decode it by hand myself(now I save 60\$).
There are lot of keys on the remote, therefore it is not this dump but the data structure i'am looking fore.
You think the same as my first guess 8bit=1byte but maybe Panasonic have some special structure in the ir code.

Hints?

scrat:
It is important that you tell us if this signal is taken from the LED voltage or the logic chip (MCU or other) IO pin. Usually there is some encoding in the middle: IR signaling is usually modulated on top of a square-wave carrier, so that anything that is not varying at a certain frequency (36kHz, a site says) is not considered to be signal. This is to make transmission more robust.
However, 1/(2*435us) -> 46kHz is not a standard frequency
http://en.wikipedia.org/wiki/Consumer_IR

Perhaps your timing measure could be not that accurate, and the signal is a 36kHz standard one. Look on the net for RC-5 and RC-6 standards.

hmmpic:

I now hook a ir-transistor and a normally scope(Rigol) to look at the freq. It is 36Khz!

Then I use a logic analyzer and a IR-module with 36Khz (SFH5110-36) and here are some logic dump.

The IR1 and IR2 is one key press on the remote!
IR1 is send first and is _not_ changing at all, all time the same.
IR2 is the part there change with the key on the remote.

I looked at the RC6 code but this will not fit in it.

You see a marker "C" on both dump, it is the overlap in the too print!

IR1:

IR2