Device Ini Editor

[kwrobel]

I think it says locked=0. However, I believe I found one part of the problem. I took a closer look at the config.exe-native.log file and found the following repeating error during scanning:

2008-04-08 10:12:46.806 VERBOSE KSPROPSETID_BdaDigitalDemodulator is NOT supported!!!
2008-04-08 10:12:46.806 ERROR PropSet->Set() failed... hr=80070492
2008-04-08 10:12:46.807 VERBOSE ServiceID: -1, PMT PID: -1, VPID: -1, APID: -1


I have attached a zip file containing both config.exe logs as well as bda.ini and qam.ini for your reference. The device I'm using is the first entry in bda.ini. I hope you can shed some light on this qam tuning misery.

By the way, I found on an unrelated forum that a user had more success getting his BDA 2870 device (he's in Europe using DVB-T) to scan properly by uninstalling the Arcsoft Totalmedia software, which according to his post had locked the driver (?). So I did the same just to be safe. So now, all I have installed is the actual BDA driver that came with the CD. Here's the reference to that post: http://forums.nextpvr.com/showthread.php?t=17101 (#7).

[sub]

I think it says locked=0. However, I believe I found one part of the problem. I took a closer look at the config.exe-native.log file and found the following repeating error during scanning:

2008-04-08 10:12:46.806 VERBOSE KSPROPSETID_BdaDigitalDemodulator is NOT supported!!!
2008-04-08 10:12:46.806 ERROR PropSet->Set() failed... hr=80070492

This tells me your device is incompatible with the "TUNING_SPECIAL=2".

Sorry, it sounds like you're out of luck on this device.

[kwrobel]

This tells me your device is incompatible with the "TUNING_SPECIAL=2".

Sorry, it sounds like you're out of luck on this device.

Sub,
I actually found this very revealing article in the EETimes posted May 2006:
http://www.eetimes.com/news/latest/showA...=187201881

In it, the author dissects the anatomy of the very similar Pinnacle PCTV USB Stick, which does DVB-T. Now I found it very interesting to see that the eMPIA 2870 chip is actually the last component in this whole scenario. Seeing that the Pinnacle is actually in the list of digital USB tuners in GB-PVR, I wondered.

I think the problem with my stick is the second component mentioned in that article, which is an Intel CE6353 DVB-T demodulator. Tonight, I will open up my USB dongle and try to identify the demodulator on that board. Since I'm in the USA and we use ATSC/QAM, I bet its the Intel CE6210 DVB-C demodulator for Cable (see Intel's list of demodulators here: http://www.intel.com/design/celect/dtcom...tm#anchor3).

Would this help the developers of GB-PVR implement supported this device?

[sub]

Would this help the developers of GB-PVR implement supported this device?

Sorry, no it doesnt. GB-PVR is entirely separated from the hardware by the BDA drivers. If this device doesnt work with "TUNING_SPECIAL=2", then the only thing that will get it going with QAM is information from the manufacturer on how they've implemented QAM tuning in their BDA drivers.

[kwrobel]

Sorry, no it doesnt. GB-PVR is entirely separated from the hardware by the BDA drivers. If this device doesnt work with "TUNING_SPECIAL=2", then the only thing that will get it going with QAM is information from the manufacturer on how they've implemented QAM tuning in their BDA drivers.

So you're saying that there is a layer of abstraction (the BDA driver), but GB-PVR doesn't know how to set the correct switch for demodulation. Did I get that right?

Judging from the Device Manager in Vista, Kworld is actually using reference drivers from eMPIA. How can I aid in getting more information about the BDA driver's internal workings? I love to dig, and seldom take "no" for an answer. I bet you it's a matter of flipping a switch in the software (my simplified view; I'm an application programmer). Anyway...

According to Microsoft's BDA Interface description (http://msdn2.microsoft.com/en-us/library...S.85).aspx), two methods deal with Modulation Types: get_ModulationType and put_ModulationType. The types are listed as: http://msdn2.microsoft.com/en-us/library...S.85).aspx

According to HDHomerun's web page for my zip code (http://www.silicondust.com/hdhomerun/lin...code=60545), Comcast uses 256-QAM. So the modulation type should be set to BDA_MOD_256QAM (or 11 as INT value). Of course I don't know how GB-PVR utilizes the TUNING_SPECIAL directive internally, but would THAT help the developers?

[sub]

So you're saying that there is a layer of abstraction (the BDA driver), but GB-PVR doesn't know how to set the correct switch for demodulation. Did I get that right?

Yes. The manufacturer most likely has some private proprietary interface for control QAM tuning (much like VistaView and OnAir).

Judging from the Device Manager in Vista, Kworld is actually using reference drivers from eMPIA. How can I aid in getting more information about the BDA driver's internal workings?

Pretty much all you can do is ask the manufacturer to supply the information.

[kwrobel]

I'm not getting anywhere with this dongle. Just for kicks, I installed SageTV Trial yesterday and it wouldn't find any channels either, though it recognized the device as BDA 2870 Tuner.

Also, I opened the thing up today, and it utilizes different chips that are hard to get information about. Just for the record to anybody interested, the dongle consists of:
* eMPIA EM2870
* LG Electronics LGDT3304
* NXP TDA18271HDC1

That's about all I could find out hardware-wise. Now how would I have to approach KWorld about the driver? What information would they have to provide about their driver in order to make it work?

[sub]

You'd have to find an email address on the kworld website, then email them to say that you're trying to use GB-PVR with this device, but its currently able to perform QAM tuning with this device, and the author of GB-PVR had indicated he would need information from kworld about their implementation of ClearQAM tuning on their BDA drivers.

You'll probably never hear back, but its worth a shot. Its worked for other users in the past.

[whurlston]

I think he meant:

but its currently unable to perform QAM tuning with this device

[sub]

yep