to copy the code of an IR remote

[humanus]

I want to observe the pulse train of an Ir remote code and after that to copy it with the same timings and periods. I only need a single pulse train to copy. But first of all I want to be able to observe a pulse train permanently on a digital scope (I have Rigol DS 5022M). But I could not succeed to observe the stored pulse train statistically on the screen. Is there anybody to explain how I can observe the pulse train of an IR remote (at least 32 bits).

 

[Nigel Goodwin]

Use an IR receiver IC - monitor the output of that on your digital scope, you don't need to know about the actual IR pulses themselves.

What is your IR remote?.

 

[humanus]

My remote is an IR remote of a not standart one (like RC5, NEC or Sony). I use a TSOP1256 to observe the pulses. I do not need to observe the actual IR pulses which carries the code. I just need to observe the binary code, pulse widths, periods in order to copy the same timing with a PIC.

 

[Nigel Goodwin]

So, as you're using a TSOP it should be pretty easy to record the code on your digital scope?, what's the problem?.

 

[crutschow]

The problem may be in synchronizing the bit pattern on the scope to give a stable display. Try using the single-trace option on the scope. By suitable selection of the time-base you should be able to capture at least one single 32-bit sequence. It may not start at the first bit but you should be able to determine which is the first bit from the gaps in the sequence.

 

[humanus]

Of course I can record the code and then I can play it again. But all happens in a very short time on the screen.I want to see the pulse train as stable as a drawing on the screen (just like a slide show wihch is controlled manually) in order to measure the pulse widths and the periods of all the pulse train. By the way my scope is Rigol DS 5022 M. Thanks for the answers.

 

[KeepItSimpleStupid]

You want to go to this forum: JP1 Remotes :: Index I don't have the time to look, but I have one of the devices used to decode the IR protocol. There is a lot to learn.

 

[KeepItSimpleStupid]

I got a reasonable signal using this: **broken link removed**

 

[humanus]

Thank you very much indeed. This site is just I look for.

 

[Nigel Goodwin]

Of course I can record the code and then I can play it again. But all happens in a very short time on the screen.I want to see the pulse train as stable as a drawing on the screen (just like a slide show wihch is controlled manually) in order to measure the pulse widths and the periods of all the pulse train. By the way my scope is Rigol DS 5022 M. Thanks for the answers.

Surely a digital scope allows you to do exactly that? - in recent times I've used the PICKit2 PIC programmer to do a similar thing using it's simple logic analyser function.

You simply sync to the negative going edge, set it to record a single scan and press a button on the remote.

 

[humanus]

My scope displays approaximately a byte of the stream for about a second on the screen. I think this will be impossible with just a digital scope as one I have. So I will try something like an IR Scope.

 

[Nigel Goodwin]

My scope displays approaximately a byte of the stream for about a second on the screen. I think this will be impossible with just a digital scope as one I have. So I will try something like an IR Scope.

The specs say it's a digital storage scope, you should have no problem storing and analysing the output from an IR remote control.

It's what such scopes are designed to do - store and display one-off signals so you can easily see them.

I suspect you need to read the instructions and find out how to use it.

 

[humanus]

Thank you Nigel. I have examined the operation manual a few times, but there is not sufficient information about this kind of observation. I succeeded to observe constantly a small part of the bit stream, but I could not examine the rest step by step. I am a newbie about digital scopes.

 

[Nigel Goodwin]

Thank you Nigel. I have examined the operation manual a few times, but there is not sufficient information about this kind of observation. I succeeded to observe constantly a small part of the bit stream, but I could not examine the rest step by step. I am a newbie about digital scopes.

I've never used one either - but you should be able to trigger it from a single event and store the result, then expand and examine it.

 

[Nigel Goodwin]

OK, I've attached the instruction manual for you (just in case it's different), have a look at example 3.3 - but set the triggering to falling, not rising.

 

[humanus]

This manual differs from mine in order to have an example about the problem I have. Finally I have succeed to observe the full stream Many thanks for all who replied, specially Nigel.