[linux-dvb] QAM 256 starts kicking out VDR widespread TT/FuSi FF cards / on AGC, etc, IMPL and Filter Optimisation

Marco Skambraks marco at ammec.de
Wed Aug 2 20:17:24 CEST 2006

I tried your patch with TT dvb-c 2.1 premium and the latest firmware 2623
kernel 2.6.13 and almost the latest dvb/v4l drivers
my cable-provider is iesy (hessen)
frq = 121mhz qam256
for NTV and some of the other private-channels
the patch has no effect I've still several drop-outs
if I watch a channel with qam256 modulation

maybe I can support you with some debug output
just tell me which data is important to improve the qam256 support in 


On Wed, 2 Aug 2006, thomas schorpp wrote:

> patch contains correction for viterbi monitor flag, wrong SYNC register bit
> used before in ves1820.c(?).
> cant use hg head - doesnt build dvb-ttpci.ko dont know why, yet.
> y
> tom
> <schorpp> lo
> <schorpp> I am on the qam256 problems with some FF cards dvb
> <schorpp>
> <schorpp> created a diagnostics patch for ves1820.c
> <schorpp> after trial'n'error with AGCCONF register the register readings are
> wrong although the register accepts my values
> <schorpp> Aug  2 14:51:28 tom1 kernel: ves1820: VAGC 0xff
> <schorpp> Aug  2 14:51:28 tom1 kernel: ves1820: AGCCONF 0x13
> <schorpp> Aug  2 14:51:28 tom1 kernel: ves1820: PWMREF 0x13
> <schorpp> it always reads 0x13 whatever i write to the reg
> <schorpp> may the av7110 firmware interfere?
> <schorpp> not opened the box yet
> <schorpp> PIN VAGC is connected to AGC input of fusi dvb-c, right?
> <schorpp> seems no regulation IMPL
> <schorpp> dev-list says why
> <schorpp> many different tuners
> <schorpp> source says of a pwm data member
> * timonator (n=timonato at p508557F3.dip.t-dialin.net) has joined #linuxtv
> <schorpp> it is configured used to control PIN FEL
> <schorpp> what do you control with pwm value?
> <schorpp> ADC input of tuner PLL?
> <schorpp> ?
> <KeefR> aren't there some registers, that are write-only?
> <schorpp> KeefR, yes but..
> <schorpp> none of those i used
> <schorpp> and no if then only read only
> <schorpp> ...
> <schorpp> 1st i want to try is AGC working
> <schorpp> 2nd filters adaption if neccessary
> <schorpp> need AGC cause incoming signal is out of ADC capture range
> (clipping)
> <schorpp> ves1820 ADC
> <schorpp> Aug  2 14:51:28 tom1 kernel: ves1820: VAFC -3
> <schorpp> normal, works on qam64 channels
> <KeefR> got a ves1820, too, but qam256 works here
> <schorpp> KeefR: manufacturer and type of card, driver version?
> <schorpp> cable provider? ;)
> <schorpp> which
> <schorpp> ...
> <schorpp> yes much things DO WORK FOR ME too ;)
> <schorpp> ok showing code..
> <schorpp> heres the diag patch:
> <schorpp> http://paste.lisp.org/display/23544
> <schorpp> http://pastebin.com/761837
> <schorpp> pls review
> <KeefR> schorpp: hauppage dvb-c rev 2.1, kable-bw, cvs driver (6ebb57bfac7d)
> <schorpp> old cvs or hg ?
> <schorpp> :)
> <schorpp> list states there were problems with this card <schorpp> around may
> 06
> <schorpp> interesting
> <KeefR> hg
> <KeefR> but i have probs tuning to higher frequencies, not enough snr, some
> channels aren't even revognized
> <schorpp> no relevant changes for this problem head
> <schorpp> probs?
> <schorpp> which cable provider? 2nd Q
> <KeefR> kabel-bw
> <schorpp> me too :o
> <schorpp> <-- karlsruhe süd
> <KeefR> status 1f | signal ffff | snr ecec | ber 00100824 | unc 00000001 |
> <KeefR> fta radio with 256qam at 650mhz
> <schorpp> ber too high
> <KeefR> muehlburg ;-)
> <KeefR> it works
> <schorpp> hehe
> <KeefR> but higher than 650mhz there are more probs, orf with 256qam at 450mhz
> is no probs
> * schorpp gives KeefR a cold fresh beer
> <KeefR> no beer today...had enough the last two days
> <schorpp> *whine* cant get orf1
> <schorpp> FE: VLSI VES1820 DVB-C (DVBC)
> <schorpp> status SCVYL | signal ffff | snr ecec | ber 004bb310 | unc ffffffff
> <schorpp> status SCVYL | signal ffff | snr e3e3 | ber 004dc0d8 | unc ffffffff
> <schorpp> :(
> <schorpp> house amp is wisi vx63
> <KeefR> status 1f | signal ffff | snr eeee | ber 0002fc42 | unc 00000000 |
> <KeefR> orf1
> <KeefR> don't know about the house amp
> * schorpp gives KeefR a coffee
> <schorpp> go downstairs ;)
> <KeefR> but normal cables didn't work, had to make one myself
> <schorpp> yeah me too, from mükra shop
> <schorpp> unchristian expensive :[
> <KeefR> well, last weekend i bought one at familia...10 euro for 3m, but that
> one works as well as my selfmade
> <schorpp> :/ LOL
> * alan|philo has quit ("Leaving")
> <KeefR> i'm thinking about buying an amplifier
> <KeefR> but I'll probably try to rent a dvb-c receiver first and check with
> that one
> <schorpp> yeah
> <schorpp> me too looking for someone who has got latest kabelbox version
> <KeefR> at least the house amp isn't limited to 450mhz

AMMEC - Accessible Multimedia Entertainment Center 

Email: Marco Skambraks <marco at ammec.de>

More information about the linux-dvb mailing list