From sperez@pipeline.com Sat Apr 08 16:29:33 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pipeline!sperez From: sperez@pipeline.com (Sergei Pérez) Newsgroups: comp.dsp Subject: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr08.162933.9415@pipeline.com> Date: Sat, 08 Apr 1995 16:29:33 GMT Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. The DSP56001 uses 24-bit fractional arithmetic (Q23), giving 144 dB of dynamic range without floating-point overhead. This leaves over 95% of the DSP56001's 16.5 MIPS available for other audio tasks. Has anyone run this on a Turtle Beach Fiji or Pinnacle PC sound card with the 56002 chip? -- Sergei Pérez *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0 From akim@stanford.edu Mon Apr 10 11:17:33 1995 Path: ashpoly!cascade!brgate!saturno!stanford!akim From: akim@stanford.edu (Astrid Kim) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr10.111733.7514@stanford.edu> Date: Mon, 10 Apr 1995 11:17:33 GMT References: <1995Apr08.162933.9415@pipeline.com> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Apr08.162933.9415@pipeline.com>, sperez@pipeline.com (Sergei Pérez) writes: > Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- Astrid Kim -- Stanford University Computer Systems Lab "The hatch is open. Is anyone listening?" From cduarte@unam.mx Wed Apr 12 12:11:33 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!cduarte From: cduarte@unam.mx (Callum Duarte) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr12.121133.1860@unam.mx> Date: Wed, 12 Apr 1995 12:11:33 GMT References: <1995Apr08.162933.9415@pipeline.com> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: Netscape 1.1N Lines: 12 In article <1995Apr08.162933.9415@pipeline.com>, sperez@pipeline.com (Sergei Pérez) writes: > Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. > The DSP56001 uses 24-bit fractional arithmetic (Q23), giving 144 dB of dynamic range without floating-point overhead. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Callum Duarte Zyxel U-1496E @ ISDN 64k bps "A soul is not exclusive to biology." From ohernandez@pacbell.net Thu Apr 13 12:46:33 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!pacbell!ohernandez From: ohernandez@pacbell.net (Olga Hernández) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr13.124633.8316@pacbell.net> Date: Thu, 13 Apr 1995 12:46:33 GMT References: <1995Apr08.162933.9415@pipeline.com> <1995Apr10.111733.7514@stanford.edu> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Apr10.111733.7514@stanford.edu>, akim@stanford.edu (Astrid Kim) writes: > Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Olga Hernández "Tape doesn't lie at 02:14. Ears do." Sun 3/60 (SunOS 4.1.1) / Linux 1.2.13 From mlee@ox.ac.uk Sat Apr 15 08:27:33 1995 Path: ashpoly!cascade!brgate!saturno!ox!mlee From: mlee@ox.ac.uk (Matthias Lee) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr15.082733.4975@ox.ac.uk> Date: Sat, 15 Apr 1995 08:27:33 GMT References: <1995Apr08.162933.9415@pipeline.com> <1995Apr12.121133.1860@unam.mx> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Apr12.121133.1860@unam.mx>, cduarte@unam.mx (Callum Duarte) 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. -- Matthias Lee Opinions expressed are solely my own and not those of Oxford University Computing Laboratory. ------------------------------------------------------------