How do GB-PVR start the external channel changer?

[blader_se]

Using the USB-UIRT command line tool to change channels fails for me (see thread USB-UIRT InterCodeDelay - does it work?)when a recording starts. Everytime else it works (from the TV guide etc). Switching to channel 12 results in two changes, first to channel 1 and then to channel 2, i.e. there is a too big delay between the invokations to uutx inside the bat file.

What are the GB-PVR doing differently while starting a scheduled recording vs plain channel changing reagrding cpu/disk usage?

So could I make the call for channel changing be made with a higher priority, in blocking mode or something, just to get it the cpu it needs to switch to the correct channel?

I know I'm pretty alone with this really stupid reciever so I understand if you don't want to do anything about it, but I really would like to know what's going on. (I've also asked Jon if he could make a special version of uutx that can send more than one code in a single invocation.)

[sub]

What are the GB-PVR doing differently while starting a scheduled recording vs plain channel changing reagrding cpu/disk usage?

One is run from the users account, the other is run in the user account the recording service runs as (usually localsystem).

What does the utility do? I know some people have had problems with .exe channel changer utilities that try to talk to some other app to get it to communicate to the device (a server or tray app or similar). The reason this was a problems is they were transferring data using WM_COPYDATA, which is essentially via the clipboard. The clipboard is not shared between the user's desktop account and the recording service, so this communication was failing.

I hope that makes sense?

[blader_se]

What does the utility do?

It just sends a single stream of bits (the one in the IR definition file) to the USB-UIRT. More explicitly, I don't know. But I think you do the same thing when sending strings to the USB-UIRT for channel changing. You call something (usb-uirt-dll?) with a button at a time, right?

The problem for me is that I need to keep track of the toggling bit manually, so I call the utility twice from my bat file, but too much time passes between the calls...
Actually the code you use to send the button code to the usb-uirt blaster, is that open? Could that be turned into a RC5-toggle-aware .exe channel-changer?

[sub]

Actually the code you use to send the button code to the usb-uirt blaster, is that open?

No, sorry. That specific is a bit of an ugly mess spread across a few files, and not easily separated. My code uses calls to unmanaged c++ code, which was the only option at the time. If I was writing this again, I'd have probably used the C# library thats now available.

Could that be turned into a RC5-toggle-aware .exe channel-changer?

I dont think that could be done easily.

You might be better trying to write a standalone executable replacement for uutx utility, but handles multiple digits, and ideally also does your RC5 toggle.

[blader_se]

OK, thanks for answering. I'll probably try and find any USB-UIRT sdk laying around and hack away...

Update: I had not seen the thread below when I posted this!

I'm going to release an sdk of sorts, which will allow people to implement their own channel changer plugins (and other things), so it might get supported that way.

(http://forums.nextpvr.com/showthread.php?t=601)