[linux-dvb] C-band Satellite IP Multicast reception question.

[Stonie Cooper <stonewall@inebraska.com>]

I know this has to be simple, but after several days of attempts, I thought I 
better put the following to this group for some insight.

I have three cards - Nova-S, Nexus-S, and B2C2 SkyStar2 (Technisat).  I'm 
attempting to lock onto a C-band multicast satellite ip.  I have an external 
modem as a verification device that works just fine with all these settings.

I think the part where I misqueue in interpreting and using the frequence and 
symbol rate - C-band is obviously different than the normally used Ku.

My L-band frequency is 1193.5MHz (the C-band is 3956.5MHz); I've attempted to 
use dvbtune and szap, and in the case of szap, dvbnet once I "thought" I had 
a lock . . . but no go.

The symbol rate is 6.349422 MSPS.  There is no audio or video PIDs - this is a 
data stream - so thus my first question:

Using szap - how do I use the channel.conf without specifying a apid and vpid?  
What I need, and use the dvbnet for, is a dpid.

In my attempts - I have tried the following config for my signal:

AnimalNews:1193:v:0:6349:0:0:1:99999

And then:

# szap -n 1

And I get:

status 31 | signal 65535 | snr 55416 | ber 0 | unc 0 | FE_HAS_LOCK
status 31 | signal 65535 | snr 55401 | ber 0 | unc 0 | FE_HAS_LOCK

Thinking I have won, I do the dvbnet to attach to the pid:

# dvbnet -d 355

And I get:


DVB Network Interface Manager
Version 1.1.0-TVF (Build Fri Dec 31 03:08:14 2004)
Copyright (C) 2003, TV Files S.p.A

Device: /dev/dvb/adapter0/net0
Segmentation fault

And further attempts get:

DVB Network Interface Manager
Version 1.1.0-TVF (Build Fri Dec 31 03:08:14 2004)
Copyright (C) 2003, TV Files S.p.A

Device: /dev/dvb/adapter0/net0
Error: couldn't open device /dev/dvb/adapter0/net0: 16 Device or resource busy

On the other cards, I get:

status 3 | signal 65535 | snr 40548 | ber 37600 | unc 0 |

And the same results as above when attempting the dvbnet.

When I am successful in getting a device attached to a PID (and there is no 
rhym or reason as to why), there is no data on those devices as seen from 
ifconfig on each device.

Finally, should the interrupts go up for this device if I have luck?  I 
cat /proc/interrupts . . . and on the Hauppauge cards, I get:

 18:          0   IO-APIC-level  saa7146 (0)

But on the SkyStar, I do see some counts:

  3:        209          XT-PIC  Skystar2

But nothing shows up in the packet counts from ifconfig.  I assume I am 
misqueuing on how to pass the freq and sr . . . as most examples I find are 
for Ku band stuff, and for higher symbol rates.

Thanks in advance for any assistance.

Stonewall