[linux-dvb] Re: KWorld DVB-t

[Jonathan Thorpe <jlthorpe@gmail.com>]

Hi Soyeb,

Since the KWorld/V-Stream card uses the same Samsung Tuner as the
AVerMedia AVerTV DVB-T 771, I decided to force the mt352 front end to
treat the V-Stream card as an Avermedia card with interesting results.

It seems that the tuner can now be controlled, but I can't grab the
stream. After testing a variety of known frequencies (these are known
to work in Windows) and A/V PIDs, dvbstream tunes in, but the
resulting output is empty.

-----
dvbstream -qam 64 -cr 3_4 -gi 16 -bw 7 -tm 8 -f 226500 -ps -n 10 -o
512 650 > /tmp/outstream.mpg
dvbstream v0.6 - (C) Dave Chapman 2001-2004
Released under the GPL.
Latest version available from http://www.linuxstb.org/
Using DVB card "Samsung TDTC9251DH01C Tuner on V-Stream Card"
tuning DVB-T (Australia) to 226500000 Hz, Bandwidth: 7
polling....
Getting frontend event
FE_STATUS:
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Event:  Frequency: 226505184
Bit error rate: 0
Signal strength: 65192
SNR: 47802
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
dvbstream will stop after 10 seconds (0 minutes)
Setting filter for PID 512
Setting filter for PID 650
Output to stdout
Streaming 2 streams
Caught signal 1 - closing cleanly.
-----

dvbtune provides similar results (in this case, it should show some
information about the subchannels):

--
./dvbtune -f 219500 -i
Using DVB card "Samsung TDTC9251DH01C Tuner on V-Stream Card"
tuning DVB-T (Australia) to 219500000 Hz
polling....
Getting frontend event
FE_STATUS:
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 0
Signal strength: 65186
SNR: 52942
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
<transponder type="T" freq="219500000">
Nothing to read from fd_pat
Nothing to read from fd_sdt
</transponder>
--

Could it be that the DVB extensions to the cx88xx driver need to be
considered, or is this still a front end issue? I'm at a complete loss
at this stage, but one thing that came to mind are the GPIOs used by
card - it's likely that those used by the Fusion HDTV card aren't the
same as those used by the KWorld card.

If this is the correct way to proceed, is there any way to get these
values without a bus analyser? Am I way off track here?


Another problem I'm having (minor in comparison), is with recognising
the V-Stream card - around line 260 in Christopher Pascoe's
cx88-cards.c driver, I attempted to add:

--
{ "Samsung TDTC9251DH01C Tuner on V-Stream Card", { 0xDE, 0x17, 0xA6,
0x08}, NULL,
	  0x50, 0xFC, 0x0F, 0xC2, 
	  { 0x31, 0x05 }, { 0x72, 0x49 }, { 0x64, 0x00 }, { 0x55, 0xB7 },
	  { { 11, 1, { 0x67, 0x10, 0x23, 0x00, 0xFF, 0xFF, 0x00, 0xFF, 0x00,
0x40, 0x40 } },	/* AGC */
	    { 2,  0, { 0xB5, 0x7A } },		/* ? Reserved register ? */
	    { 0 } },
	  83333, avermedia771_freq_to_tuner, default_tuner_to_freq, },
--

Using this, the frontend defaults to the "Unkown" option - there must
be something wrong with the IDs, but I'm not sure what.

I'd really appreciate help with getting this card working.

Thanks,
Jonathan