On 01/15/2013 04:49 PM, Antti Palosaari wrote:
I am a little bit lazy to read all those patches, but I assume it is
possible:
* return SNR (CNR) as both dB and linear?
* return signal strength as both dBm and linear?
And what happens when when multiple statistics are queried, but fronted
cannot perform all those?
Lets say SS, SNR, BER, UCB are queried, but only SS and SNR are ready to
be returned, whilst rest are not possible? As I remember DVBv5 API is
broken by design and cannot return error code per request.
OK, I read that patch still. All these are OK as there is SCALE flag
used to inform if there is measurement or not available.
No anymore question about these.
Issues what I still would like to raise now are:
1) How about change unit from dB/10 to dB/100 or even dB/1000, just for
the sure?
2) Counter are reset when DELIVERY SYSTEM is set, practically when
tuning attempt is done. There is new callback for that, but no API
command. Functionality is correct for my eyes, is that extra callback
needed?
3) Post-BER. I don't need it, but is there someone else who thinks there
should be both pre-BER and post-BER? IMHO, just better to leave it out
to keep it simple. In practice both pre-BER and post-BER are running
relatively, lets say if pre-BER shows number 1000 then post-BER shows
only 10. Or pre-BER 600, post-BER 6. Due to that, I don't see much
interest to return it for userspace. Of course someone would like to
know how much inner coder is working and fixing error bits and in that
case both BERs are nice...
4) Returning bit counts as BER and UCB means also driver should start
polling work in order to keep driver internal counters up to date.
Returning BER as rate is cheaper in that mean, as driver could make
decision how often to poll and in which condition (and return values
from cache). Keeping track of total bit counts means continuous polling!
regards
Antti
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http://palosaari.fi/
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