[linux-dvb] Re: nxt200x on AVerTVHD a180

Michael Krufky mkrufky at m1k.net
Thu Oct 27 05:42:40 CEST 2005

Kirk Lapray wrote:

> The errors you are getting are when it is trying to read signal 
> strength, snr, ucblocks, and ber.  This is usually caused by not being 
> tuned to a digital channel.  It looks like you are having some tuner 
> issues and once this is fixed you should no longer get these errors.

EXACTLY!  Now I got it working...... I'll be committing the nxt200x 
module to cvs in a few minutes.  After that, I will commit your 
v4l-kernel patch.

> As for these additional devices showing up, did you load the nxt200x 
> before these started showing up?  All the changes I made in 
> tuner-simple should only apply to the HDTV Wonder, but some of the 
> same init steps are also done in the nxt200x driver at the end of 
> nxt2004_init function under "initialize tuner."  You can see these 
> same commands in cx88-cards for the HDTV Wonder.  These commands 
> enable the tuner so it shows up on the I2C bus on the HDTV Wonder, and 
> I wonder if it is also doing this on the A180.  If this is the case 
> try using the tuning code in the nxt200x driver that writes directly 
> to the tuner instead of the code that goes through the NXT chip.

This is exactly what I did to make it work.  To save myself time, I 
renamed the TDHU2 in dvb-pll to be the same as your tuner, to trick 
nxt200x into writing to it directly.  This was just a hack to see if I 
can get a signal, and it worked!  It seems to be working just as well as 
my FusionHDTV[35] Gold.

I dont like the way that you hardcoded nxt200x to give special treatment 
to Philips TUV1236D.... I am going to commit the module to cvs exactly 
as you provided it, but I plan to make some changes.

Instead of conditionally writing directly to Philips TUV1236D, I think 
that it should handle all pll's in this manner by default.  We already 
know this works for Philips TUV1236D and Alps TDHU2.  We should instead 
have a parameter that we pass through the config struct that will 
instruct the module to go through the NXT chip when communicating with 
the pll.....  Any ideas for what I should name this parameter?

> If this is the case then support for the tuner can be added in 
> tuner-simple and you should be able to tune to analog channels.  To 
> see how I did this look in tuner-simple and cx88-cards for the changes 
> made to support the HDTV Wonder and Philips TUV1236D tuner.

I'm the guy that committed that patch of yours to v4l-kernel cvs, 
remember?  :-P

I'll take care of this aspect after I commit the dvb support for ATI 
HDTV Wonder, and after that, AVerTVHD a180 ...  I am still not convinced 
that this card has analog support.  No matter what tuner I try, all I 
get is horizontal lines.  This doesnt surprise me at all, because many 
people have reported that this card has no analog capabilities. There 
have been conflicting reports from what I've read online.   After some 
more tuner-hacking, hopefully I'll find the truth.   After I get all the 
rest of this stuff done, I'll mess with tuner-simple and see if I can 
squeeze analog video out of it.

Thanks again.

-Michael Krufky

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