From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from pne-smtpout4-sn2.hy.skanova.net ([81.228.8.154]) by www.linuxtv.org with esmtp (Exim 4.63) (envelope-from ) id 1Jg6wh-0007ca-Bj for linux-dvb@linuxtv.org; Mon, 31 Mar 2008 01:28:18 +0200 Message-ID: <47F021EB.6010104@gmail.com> Date: Mon, 31 Mar 2008 02:27:39 +0300 From: Anssi Hannula MIME-Version: 1.0 To: Thierry Lelegard References: In-Reply-To: Cc: linux-dvb@linuxtv.org Subject: Re: [linux-dvb] Interpretation of FE_READ_BER List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: linux-dvb-bounces@linuxtv.org Errors-To: linux-dvb-bounces+mchehab=infradead.org@linuxtv.org List-ID: Thierry Lelegard wrote: > Hi, Hi! I'm not an expert in this matter, but it seems no one else is replying. > What is the interpretation of the value returned by ioctl FE_READ_BER? AFAIK the exact meaning of all the values is driver/device-specific. > Normally, a bit-error-rate is something like 10^-6 (typically not an > integer value). > > There is no clue in the Linux DVB API doc. Google reports similar > questions but none with an answer. I have just seen one note suggesting > it could be a multiple of 10^-9. Looks good to me but since there is > no good definition of this parameter in the docs, I wonder if drivers > implement them in a consistent way. I don't think so. > With my Nova-T 500 (Fedora 8, kernel 2.6.24.3-12, recent v4l hg tree), > the reception is quite fine, FE_READ_SIGNAL_STRENGTH returns 40000 (60%), > but FE_READ_BER always returns 0. Does this mean "not even the slightest > error" (to good to be true), "not supported" (should return errno ENOSYS), > "driver bug"? 0 can very well mean there is no errors, it is not that uncommon (I've seen it with my devices in good conditions). -- Anssi Hannula _______________________________________________ linux-dvb mailing list linux-dvb@linuxtv.org http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb