who should be care about of corrected roll-off factor which have to send to cx24116 - the drivers or user software ? does roll-off factor = 0,35 good for 99% dvb-s2 channels ?

Goga

Alex Betis

2009-01-23 19:52 UTC #3 lore raw

Quoted 7 lines · On Fri, Jan 23, 2009 at 9:49 PM, Goga777 <[email protected]> wrote:

Quoted 3 lines
Quoted 1 line
does support cx24116 the roll-off factor = auto ?
no
who should be care about of corrected roll-off factor which have to send to cx24116 - the drivers or user software ? does
roll-off factor = 0,35 good for 99% dvb-s2 channels ?

Driver interface allows specifying AUTO value for most of the parameters. User application has no idea what card is used and what driver is running. Since there are other drivers/chipsets that can handle AUTO setting, I don't see any reason why application should not use it.

For example, DVB-S uses only rolloff = 0.35, so if the driver knows that the chip can't accept auto value, it should use 0.35 value by default in that case.

Beside all that, there is a bigger problem that pops up with cx24116 chips using S2API.
When specifying AUTO value for any of the parameters the driver fails the tuning, but the application knows nothing about it, so it thinks that current received stream is from the new channel, while its not true.

Quoted 11 lines

Goga
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Goga777

author

2009-01-23 21:36 UTC #4 lore raw

Quoted 3 lines

For example, DVB-S uses only rolloff = 0.35, so if the driver knows that the chip can't accept auto value, it should use 0.35 value by default in that case.

good idea. Anybody against ?

Goga

Christophe Thommeret

2009-01-23 22:07 UTC #5 lore raw

Le vendredi 23 janvier 2009 22:44:35 Goga777, vous avez écrit :

Quoted 5 lines

Quoted 3 lines
For example, DVB-S uses only rolloff = 0.35, so if the driver knows that the chip can't accept auto value, it should use 0.35 value by default in that case.
good idea. Anybody against ?

That's already the case with cx24116, 0.35 is used for dvb-s

Signature · 1 line

Christophe Thommeret

Goga777

author

2009-01-24 08:16 UTC #6 lore raw

Quoted 8 lines

Le vendredi 23 janvier 2009 22:44:35 Goga777, vous avez Иcrit :
Quoted 5 lines
Quoted 3 lines
For example, DVB-S uses only rolloff = 0.35, so if the driver knows that the chip can't accept auto value, it should use 0.35 value by default in that case.
good idea. Anybody against ?
That's already the case with cx24116, 0.35 is used for dvb-s

already has been done with cx24116 ? It's strange because I can see in cx24116 debug logs the messages like this

unsupported rolloff selected (3)

for dvb-s

Goga

Christophe Thommeret

2009-01-23 19:53 UTC #7 lore raw

In reply to Goga777

Le vendredi 23 janvier 2009 20:49:24 Goga777, vous avez écrit :

Quoted 7 lines

Quoted 3 lines
Quoted 1 line
does support cx24116 the roll-off factor = auto ?
no
who should be care about of corrected roll-off factor which have to send to cx24116 - the drivers or user software ? does roll-off factor = 0,35 good for 99% dvb-s2 channels ?

The scanning app should get the rolloff factor.
Yes, 0.35 is most likely.

Signature · 1 line

Christophe Thommeret