Hi Peter, (adding back the list to CC) On Saturday 12 March 2011 11:48:38 Peter Tilley wrote: > Hi Patrick, > My sincerest apologies for coming to you directly but I have tried the > Linux mailing list and received no response and noticed you seem to have > been heavily involved with much of the Dibcom driver development. > > I have an issue with a dual tuner which is sold under the brand of Kaiser > Baas KBA01004 but identifies itself as 1164:1e8c which is a Yaun device > and this device seems to have already been included in the driver files. > > It loads ok and reports not problems. It tunes ok and reports FE lock on > all channels however on all but one channel upon receiving FE lock the > BER stays at 1ffff instead of dropping to a low number which would > indicate I am not getting viterbi. > > The device is fitted with pairs of MT2266 and DIB7000 which I have > positive identified by opening the USB stick. > > am more than happy to try and work this out myself however the amount of > detail around in support of the Linux drivers is extremely low and a > search for manufacturers data sheets finds next to nothing. There > seems to be lots of what I would call "magic numbers" in the drivers and > little to determine what they are doing. Are you sure it is a driver problem? If the BER stays at this value it could also mean that the channel- configuration is wrong. Are you using a channels.conf which has all parameters set, or are you doing a channel-scan-like tune (all values are set to AUTO). > My question to you is are you able to offer either any pointers to solve > the problem or help me find detailed information about the devices so I > can help myself. > > I should point out that the device works perfectly under windows on the > same antenna and indeed I have even successfully extracted the firmware > from the supplied windows driver, renamed it so it loads and the problem > still remains. There are usually some adaptations board-designing companies do to improve reception quality (adding external LNAs and things like that) that are of course handled by the Window-driver, because it is created by the manufacturer and not by the Linux-driver, because (in this case) the driver was released by the chip-manufacturer. Is the device toggling between FE_HAS_LOCK and no FE_HAS_LOCK or does it stay constantly at Please try whether you can achieve the BER lowering by moving the antenna or using a better one. If this helps, it really means that the windows-driver does something more the board. I doubt that the chip-driver needs to be changed, more likely the GPIOs of the dib0700 (in dib0700_core.c) or of the dib7000 are used to turn on or off a frequency switch or a LNA. Good point, what are the frequencies you're tuning ? regards, -- Patrick http://www.kernellabs.com/ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
