From jlopez@cern.ch Sat Feb 12 23:54:36 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cern!jlopez From: jlopez@cern.ch (Ji-woo López) Newsgroups: comp.dsp Subject: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb12.235436.3244@cern.ch> Date: Sat, 12 Feb 1994 23:54:36 GMT Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 11 Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. This leaves over 95% of the DSP56001's 16.5 MIPS available for other audio tasks. Source code in 56k assembly uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/dsp56k/stardust_56k.asm. -- Ji-woo López Opinions expressed are solely my own and not those of European Laboratory for Particle Physics, Geneva. ------------------------------------------------------------ From kreyes@cmu.edu Sun Feb 13 10:31:36 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!cmu!kreyes From: kreyes@cmu.edu (Karen Reyes) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb13.103136.2481@cmu.edu> Date: Sun, 13 Feb 1994 10:31:36 GMT References: <1994Feb12.235436.3244@cern.ch> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Feb12.235436.3244@cern.ch>, jlopez@cern.ch (Ji-woo López) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. > By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- Karen Reyes Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS. ------------------------------------------------------------ From mschneider@cmu.edu Tue Feb 15 01:05:36 1994 Path: ashpoly!cascade!transat!ukc!fennimore!cmu!mschneider From: mschneider@cmu.edu (Morag Schneider) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb15.010536.3460@cmu.edu> Date: Tue, 15 Feb 1994 01:05:36 GMT References: <1994Feb12.235436.3244@cern.ch> <1994Feb13.103136.2481@cmu.edu> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1994Feb13.103136.2481@cmu.edu>, kreyes@cmu.edu (Karen Reyes) writes: > Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Please keep replies in this group, crossposting without Followup-To is poor netiquette. -- Morag Schneider | mschneider@cmu.edu PGP Key fingerprint: 2B11 E35D 619B E20C "Keep the channels open." From ksokolov@hanse.de Tue Feb 15 10:41:36 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!hanse!ksokolov From: ksokolov@hanse.de (Kirsty Sokolov) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Feb15.104136.3463@hanse.de> Date: Tue, 15 Feb 1994 10:41:36 GMT References: <1994Feb12.235436.3244@cern.ch> <1994Feb13.103136.2481@cmu.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Feb13.103136.2481@cmu.edu>, kreyes@cmu.edu (Karen Reyes) writes: > Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Top-posters will be placed in my ~/.killfile without notice. -- Kirsty Sokolov -- Hanse-Netzwerk Hamburg "A soul is not exclusive to biology."