From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel Vogel" Subject: AD1981B SoundMax Date: Thu, 23 Apr 2009 10:09:56 +0200 Message-ID: <000001c9c3ea$e3cbaef0$ab630cd0$@de> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_2045_4576643.1240474204189" Return-path: Received: from go-engineering.de (mail.merkur-elektronik.de [89.244.128.23]) by alsa0.perex.cz (Postfix) with ESMTP id 2B04B10383F for ; Thu, 23 Apr 2009 10:10:05 +0200 (CEST) Received: from unknown (HELO ipex-go.ra.go-engineering.de) ([127.0.0.1]) (envelope-sender ) by localhost.uu.net (qmail-ldap-1.03) with SMTP for ; 23 Apr 2009 08:10:04 -0000 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org ------=_Part_2045_4576643.1240474204189 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hello Developers, sorry if this question is off topic on this list, but I don't know where else to send the question to.=20 I'm currently developing an audio-application on an ARM board that is equipped with an AD1981B SoundMax chip. Everything works well except the build-in equalizer. Since it is impossible to get usable technical information from Analog-Device my last hope is to find someone on this list who has some experience with the chip in question. My problem started with the datasheet not telling the format of the fixed point numbers for biquad coefficients. It only states that they are 16 bit numbers with 16 bit resolution... Then, when I use an estimated value for a0 that is unequal from zero and al= l other coefficients are zero, in theory I should hear some sound when I play a PCM file (44.1kHz / 16Bit) . But there is only silence on the output when the equalizer is not muted. Is there something else I have to set up to mak= e the equalizer output pass through? Looking forward for answers. ;-) Thanks in advance! Daniel GO Engineering GmbH - Stolzenbergstr. 13/IV - 76532 Baden-Baden Gesch=E4ftsf=FChrer: Helmut Gerstner, Dipl.-Ing. (FH) Ralf W=F6rner, Dipl.-Ing. (FH) Registergericht: Mannheim HRB 201811 ------=_Part_2045_4576643.1240474204189 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel ------=_Part_2045_4576643.1240474204189--