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Topic: Using IR Codes in Hex Format (Read 47199 times) previous topic - next topic


Apr 26, 2010, 06:05 am Last Edit: Apr 26, 2010, 06:06 am by gbulmer Reason: 1
But would the modulating frequency of the LED confuse the Arduino logic?

Do you mean, would the 56KHz modulation of the LED in the XBox IR remote confuse the Arduino logic?
It depends on what the Arduino logic is.
Assuming the signal were fed into something like Timer1 input capture, or used in pulseIn, I don't think there would be a problem.

I did Google for "56khz IR Xbox remote" and got a bunch of plausible hits.

Also, what sort of issues would I be seeing if I was using a 40 kHz receiver with a 56 kHz receiver?

Well, that is a long way off, but maybe the Vishay datasheets I looked at were for their high-noise-immunity parts, so maybe 'normal' parts are more forgiving, and you were getting hunks of data? Maybe 'patches' within a pulse-train?

Having said that, I think the Vishay parts I have been using suggest only a few KHz deviation.

Sorry, I haven't got any IR remotes that far from 38KHz, which is what I've been using (and I don't have an XBox).


The patchy response would explain my difficulty. I'll look into acquiring a receiver part that takes 56 kHz, and we'll see if I get differing results. Thanks!


Please do some more thorough googling. I just typed in that query, and it looked plausible. I didn't check anything else.

If you have an ordinary IR phototransistor to hand, you could check it for real.


I figured out my problem. It was an issue of a single bit. X.X

I hooked up a photodiode to an opamp, and zapped it with the remote. We then were able to see the marks and spaces in terms of the LED pulsing on an o-scope. Using the cursors, we figured out the frequency was ~36kHz, in spec for RC6. We also figured out that the mark/space timings being picked up by the sensor and code were accurate. It all seemed like a giant brick wall. What was going wrong? :-?

We then found out something interesting. As we continually zapped the remote with the same button, we noticed that one of the hex values kept oscillating between 7 and F. Initially stumped, we remembered that our IR library did not send the toggle bit--we had to do that manually. Hence, 7 (0111) and F(1111). So we would have to send both codes as a pair for it to work.  :o

Once I get a chance to try this, i'll let the community know if it works. Since this topic has strayed far from its original intent, I'll create a new topic with the code (if it works) and an explanation of what i'm doing and how I got this to work. :) I'll post a link to it from here.

Thanks for the support! It's been a great help.


Hi there,

I am working on a project to code my PDA as a remote control for my tv.
The TV is a samsung... I am struggling to find anything online that can help to do this.
At the moment I need to know what is the Samsung IR codes and format used?

I am using an osciloscope to read the signal from the original remote. But this as also been difficult to understand.
How do I decode this signal?

I have visited remotecentral.com and seen the hex codes.. how can I apply these to my project..(I am guessing I would need to translate these hex codes into binanry?)

Would like to hear from one you.



Is your PDA an Arduino? If not, you are in the wrong forum. If it is, place post a link to the Arduino PDA that you have.
The art of getting good answers lies in asking good questions.

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