Limitation with NIRT

I am using a NIRT to control some AV gear in a home cinema. I have successfully learned the remote codes and downloaded them to the NIRT.

It seems that the CIRCA programming limitation, of a minimum 4 frames of infrared code, is causing some problems with the High Definition Set Top Box. The HD Box is a DGTEC 5000i and it will auto repeat any key held down for more than 3 frames, a glaring mistake on DGTEC's behalf, having no delay before accepting repetition. This results in the unit (90% of the time) receiving double commands, with an obviously infuriating result.

Is there any way of reducing the minimum frame count in CIRCA or manually modifying the IR protocol to reduce the amount of information sent.

 

how have you set your key switch to switch the set top box?
If you use a bel lpress does it still send too much information?

 

The minimum/maximum frame count is set by the IR Reader software when it
learns the IR codes, not the Circa software.
To work around this problem the learned IR XML file can be edited by hand
(using notepad or similar) to change the minimum number of frames in that
protocol. On the end of the data in the learned file is the protocol
information. There is a entry called MinFrames which the IR Reader sets to
4 by default. This can be changed to 3 and then the IR library re-built to
include this file.
Now when the IR codes are used the default frame count will be 3 frames in
stead of 4.

Can't take credit for this I just cut and pasted an e-mail response from Newman (who is currently holidaying on the 'Saucy Sue' off Hong Kong with Pope Gregory IIV, the English Cricket squad and the Balinese Goddess of Plenty)

 

Ha!

If you call working in China, being told that your wife has written off the car back in Australia, getting a dose of food poisoning, and getting stuck at the outer border of Shenzhen and not being let back into the city "holidaying on the 'Saucy Sue'" then I guess that means it's a kind of holiday!

Besides, who on earth would check their work email account whilst on holidays???? Now, about the English Cricket Squad.....

 

Sorry to hear that Newman

I could lend you an Austin 1800 Ute if you were interested

And I've got a great lead on some J Series Bedfords up in Tanunda that could be right up your alley She'll be hard pressed to write one of those off...

 

Tweaking IR commands

Thankyou all for your assistance. For some reason my forum options had been reset and I didn't realise you'd replied until now, when I had just discovered the solution for myself and was about to post it.

I had just been browsing an XML file when I noticed the minframe setting and adjusted it to 2 frames. This has produced the desired effect with a now reliable control of the DGTEC HD Set-Top Box.

I had actually called CIS support and asked whether this could be done and met with the usual, "No, there's no way". I thought momentarily, it must be a hardware limitation, not the usual educational one.

OK, so who knows how to edit the IR Codes?

I'm sure everyone who's tried integrating IR products knows the frustration of having equipment with a toggling power function, never knowing whether you've just switched the appliance on or off. The good news is that most appliances have what are known as "Discreet" IR codes for "On" and "Off"

I've been looking over the site RemoteCentral and have found codes for discreet control of "on" and "off" functions for many components. Unfortunately the IR Codes in the XML files don't appear to use any recognisable format.

I'm hoping someone can tell me how RC5 protocol
AaAaAaBaAaAaAaAaAbAaBaA in the XML file
relates to hexadecimal
5001 0000 0000 0002 0010 000C

The discreet "off" code is a simple extension, in hexadecimal
5001 0000 0000 0002 0010 000C 0002 0000

If no-one can relate the two, there is one other light in the tunnel, however dim or expensive. Buying a Phillips Pronto or similar programmable remote control, I could download or create the IR commands manually and then have Circa learn them from the Pronto.

Any ideas?

 

If you don't get anywhere with the discreet on/off codes another alternative could be a detector such as this http://www.smarthome.com/8013.HTML You could plug it into a GIM module or Minder if you have one.

This one looks for a LED to be either on or off, but there are also others that work differently.

 

The hexadecimal string is a proprietary format of the Philips Pronto device. Philips refuse to disclose how to decode this data however I have heard that it has been successfully reverse engineered, at least in part.

Unfortunately we are not able to help you with respects to converting the Circa IR code files into the Philips Pronto format.

BTW, if it's a standard RC-5 type device that you're trying to control then you might have some success using the RC-5 code library that is provided in the default Circa library. The files are called Philips_RC5_xxx.

 

Hi Guys
I have similiar issues with my LG TV and what i have done was to save two consectutive presses of a single button ie power ,so one code had the toggle set and the other has it reset...

I also use my own probe system to detect tv dvd vcr statuses using either led detector or video detector....so i sent power on/off 1 wait check status via probe system and if not correct send code 2 ....works quite well......check out the website....

http://www.armaghelectrical.com.au/

HTH
Frank

 

IR HEX Code

A bit on Hex code IR if you are really interested . . .

The HEX Code IR is made up of a number of components, the first 4 hex groups of 4 characters give you the code structure and the remaining pairs give you the actual data code to be sent.

Group 1 is usually '0000' meaning it is a RAW data IR, anything else means it is a learnt code. I've not seen anything other than '0000' myself.

Group 2 gives you the carrier base frequency. Convert the HEX to decimal, then divide 1000000 by (the decimal x 0.241246). Unless you have some B&O or BOSE gear, it will usually be between 35 and 41 kHz.

The main data part is divided into data sequences, Group3 will give you the number of data pairs (ons and offs) in sequence 1 and Group4 will give number of pairs in sequence 2. Usually the problems in learning IR is the repeating of sequence pairs and capturing them correctly.

The rest of the data is basically time codes for how long the IR LED will be on and off. The first pair is always and on, then an off, and keep repeating. If you convert the HEX to decimal they are always a multiple of some base number, this is the number of time periods the signal is on or off.
The C-Bus IR text string uses a capital letter for an on time period and a lower case for an off time period. Each letter represents a different time for hte on or off. If you look in the XML file the vocab element bit gives you the time period for each letter.
The C-Bus IR always ends in an On.

You can get really tricky and paste IR codes togther to create a long string or macro, providing the carrier frequencies are similar (witihin about 5%). IR is suppose to work within 10% of the base carrier frequency, some devices are better than other when not at their exact frequency. Sometimes changing the frequency slightly will get codes to work the otherwise would not.

I do have a spreadsheet to convert HEX to C-Bus IR, but that would be giving away too many secrets and the interface is very basic at the moment (not enough time to finish it, but it does work)

Gavin

 

Thankyou Gavin,

That was all that was required to clue me in to how the IR commands are coded in the xml files.

I have now found/converted/written and tested about 8 'Discrete' codes, on a number of devices, with great success and will start a new thread spreading the good word.

Will

 

Try this link

http://www.cbusforums.com/forums/showthread.php?t=911&highlight=circa