[linux-dvb] Technotrend common interfaces think my CAM is invalid

Oliver Endriss o.endriss at gmx.de
Sun Apr 13 03:23:03 CEST 2008

P. van Gaans wrote:
> On 04/08/2008 10:28 PM, Morgan Tørvolt wrote:
> >> Knoppix didn't want to start (couldn't read the CD, not sure why, maybe
> >>  too old), but I found a Ubuntu 7.04 live/install CD. Started with that,
> >>  no difference. I did find something else: I've got three different
> >>  lenghts CI cables. One approx. 60cm, a few others approx. 40cm and some
> >>  approx. 4cm. With 60cm, both the offical Mediaguard CAM and Xcam won't
> >>  initialize. With 40cm, the Xcam still won't and the Mediaguard will init
> >>  about 50% of the time. With 4cm, both Xcam and Mediaguard will always
> >>  init. But it still doesn't work properly, even with the 4cm cable I
> >>  couldn't get a picture with the Mediaguard, and I had a picture for
> >>  about half a minute with the Xcam after which Kaffeine would freeze.
> > 
> > Not surprising. Many of the CAMs are really picky about timing and signalling.
> > The Conax 4.00 cam works every time for me. What I suggest is that you
> > try the patch I have linked to from
> > http://www.linuxtv.org/wiki/index.php/TechnoTrend_TT-budget_S-1500#CAM_tests
> > Which is this:
> > http://www.linuxtv.org/pipermail/linux-dvb/2007-July/019116.html
> > 
> > There is some manual labour to get this patch working, but once done,
> > all the CAMs I have initializes perfectly. I have no idea if the
> > cable-length affects the process less after the patching, but it sure
> > helps on initializing the CAMs I have.
> > 
> >>  I'm not sure if it's a driver problem, all I know is that this started
> >>  right after installing a new v4l-dvb a few weeks ago. The problem seems
> >>  to have no cause:
> >>
> >>  Not the DVB-card, as the S2-3200 had the same problem.
> >>  Not the CI cable, tried many different cables and I don't believe they
> >>  are all broken the same way.
> >>  Not the CI-daughterboard, I even bought new ones with no result.
> >>  Not the current v4l-dvb loaded, because a Ubuntu 7.04 live CD (kernel
> >>  2.6.20 iirc) has the same result now.
> >>  Not the computer, because the setup didn't work in another computer either.
> >>  Not the CAM, all CAMs work fine in a Vantage standalone.
> >>
> >>  And note I have used this setup, S-1500+CI+long cable+Xcam for months
> >>  without any problems.
> > 
> > You said you changed your powersupply. To a more powerful one? Some
> > PSUs does give away troublesome noise, especially when heavily loaded.
> > Also, some powerful PSUs have much of the power on wrong voltages, or
> > spread across different cables, so that you might actually be pushing
> > the PSU to it's limits on one circuit, while swapping some power
> > cables would solve the whole issue.
> > 
> > BTW, the CI daughterboard is very simple, like in _very_ simple. It is
> > very unlikely that this will break. If something is broken with CI, it
> > would probably be the cable or the tuner-card.
> > 
> > -Morgan-
> > 
> Yeah, more power! Another computer (AMD Geode NX1750 and a laptop 
> harddrive, the 480W Antec is very very bored) gives the same result. My 
> regular computer was turned off when I tested that. The patch made no 
> difference whatsoever. The Xcam is actually not picky at all, it is well 
>   known for working in pretty much any receiver - and it does. For 
> example, KNC1 CI's are quite picky but the Xcam has no problems with 
> that. Even the Matrix Reborn won't run in a KNC1, yet the Xcam does.
> I installed the card on Windows to test a bit. I also noted the CI works 
> better on Linux when I fold the CI cable in tinfoil. Here's an overview 
> of some tests:
> *Windows, unshielded 40cm cable:
> Xcam sometimes takes a while to init, but works on all tested channels 
> after that (including RTL4 and RTL5).
> Matrix Reborn: similar result.
> *Linux, v4l-dvb from hg april 12, 40cm cable in tinfoil:
> Xcam does init and works. But RTL4, RTL5 
> (http://nl.kingofsat.net/pack-canaldigitaal.php) give only sound. The 
> videoPID is correct and I did a rescan. Audio is gone if I remove the 
> CAM, so it is encrypted.
> Matrix similar result, no picture on RTL4 and RTL5 here either, but 
> apart from that it seems to work.
> *Linux, v4l-dvb from hg april 12, unshielded 40cm cable:
> Xcam does not init anymore. Not at all. Just "Invalid PC card inserted :(".
> Matrix Reborn does init, but init fails sometimes as well. When it does 
> init, I can watch most channels.. But not RTL4 or RTL5 (only sound).
> SCM Conax 4.00e: init sometimes, but can't even get into the menu. Don't 
> have a Conax subscription card right now.
> RTL4 and RTL5 do work on Windows or a standalone receiver with CI. I 
> also tried to disable all the power in the house and did a test with 
> UPS, but the Xcam still would not init with the unshielded cable. So no 
> electrical devices in the house went bad. The UPS or display are not the 
> source either, tried unplugging them. And a S-1500, T-1500 and S2-3200 
> are all doing the same thing. I've also got a Aston 1.05 and official 
> Mediaguard CAM to test if required.

Interesting that the CAM works on windows and failes on linux,
and shielding makes a difference.

Maybe we should try to play with a different debi timing.

In budget-ci.c the CAM timing is controlled by 2 lines:

#define DEBICICTL               0x00420000	-> 1 wait state
#define DEBICICAM               0x02420000	-> 9 wait states

You might try the following:
1) Change DEBICICTL to the same value as DEBICICAM (0x02420000)
   Any improvement?
2) If it does not help, try value 0x03c20000 (15 wait states) for both
   constants. Does it help?


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