From kgarcia@delphi.com Thu Feb 17 04:09:44 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!kgarcia From: kgarcia@delphi.com (Karen García) Newsgroups: comp.dsp Subject: Question: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb17.040944.3491@delphi.com> Date: Thu, 17 Feb 1994 04:09:44 GMT Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 11 Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. This leaves over 95% of the DSP56001's 16.5 MIPS available for other audio tasks. However, when downsampling from 44.1 kHz to 64 Hz, accumulator overflow in the biquad IIR filter can destabilize the loop. Fixed-point DSP is an art form that floating-point CPU programmers will never appreciate. -- Karen García Practical Peripherals 14.4 @ 33,600 bps "Row 14. No joke." From srodriguez@delphi.com Fri Feb 18 04:51:44 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!srodriguez From: srodriguez@delphi.com (Steve Rodríguez) Newsgroups: comp.dsp Subject: Re: Question: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb18.045144.5691@delphi.com> Date: Fri, 18 Feb 1994 04:51:44 GMT References: <1994Feb17.040944.3491@delphi.com> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Feb17.040944.3491@delphi.com>, kgarcia@delphi.com (Karen García) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- Steve Rodríguez | srodriguez@delphi.com PGP Key fingerprint: 10F6 1575 BD1C 236A "Keep the channels open." From akim@cern.ch Sat Feb 19 09:35:44 1994 Path: ashpoly!cascade!mxgate!coyoacan!cern!akim From: akim@cern.ch (Aiko Kim) Newsgroups: comp.dsp Subject: Re: Question: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb19.093544.9384@cern.ch> Date: Sat, 19 Feb 1994 09:35:44 GMT References: <1994Feb17.040944.3491@delphi.com> <1994Feb18.045144.5691@delphi.com> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1994Feb18.045144.5691@delphi.com>, srodriguez@delphi.com (Steve Rodríguez) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Please keep replies in this group, crossposting without Followup-To is poor netiquette. -- Aiko Kim Opinions expressed are solely my own and not those of European Laboratory for Particle Physics, Geneva. ------------------------------------------------------------ From jdubois@hanse.de Sun Feb 20 00:35:44 1994 Path: ashpoly!cascade!brgate!saturno!hanse!jdubois From: jdubois@hanse.de (Ji-woo Dubois) Newsgroups: comp.dsp Subject: Re: Question: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb20.003544.9172@hanse.de> Date: Sun, 20 Feb 1994 00:35:44 GMT References: <1994Feb17.040944.3491@delphi.com> <1994Feb18.045144.5691@delphi.com> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1994Feb18.045144.5691@delphi.com>, srodriguez@delphi.com (Steve Rodríguez) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Ji-woo Dubois -- Hanse-Netzwerk Hamburg "A soul is not exclusive to biology." From lnilsson@pacbell.net Tue Feb 22 02:55:44 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!lnilsson From: lnilsson@pacbell.net (Lars Nilsson) Newsgroups: comp.dsp Subject: Re: Question: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb22.025544.4927@pacbell.net> Date: Tue, 22 Feb 1994 02:55:44 GMT References: <1994Feb17.040944.3491@delphi.com> <1994Feb18.045144.5691@delphi.com> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 8 In article <1994Feb18.045144.5691@delphi.com>, srodriguez@delphi.com (Steve Rodríguez) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- Lars Nilsson Tape trading list upon request. SASE required for international mail.