From mmartinez@kiae.su Sun Sep 24 07:31:02 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!kiae!mmartinez From: mmartinez@kiae.su (Min-jun Martínez) Newsgroups: comp.dsp Subject: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Sep24.073102.8906@kiae.su> Date: Sun, 24 Sep 1995 07:31:02 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 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. By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. Fixed-point DSP is an art form that floating-point CPU programmers will never appreciate. -- Min-jun Martínez "Marcus is not one man." Pentium 90 (OS/2 Warp) / Linux 1.2.13 From joliveira@kiae.su Sun Sep 24 10:04:02 1995 Path: ashpoly!cascade!bigsur!kiae!joliveira From: joliveira@kiae.su (Julien Oliveira) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Sep24.100402.4941@kiae.su> Date: Sun, 24 Sep 1995 10:04:02 GMT References: <1995Sep24.073102.8906@kiae.su> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Sep24.073102.8906@kiae.su>, mmartinez@kiae.su (Min-jun Martínez) 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. -- Julien Oliveira Tape trading list upon request. SASE required for international mail. From asokolov@pacbell.net Mon Sep 25 02:46:02 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pacbell!asokolov From: asokolov@pacbell.net (Astrid Sokolov) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Sep25.024602.8727@pacbell.net> Date: Mon, 25 Sep 1995 02:46:02 GMT References: <1995Sep24.073102.8906@kiae.su> <1995Sep24.100402.4941@kiae.su> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1995Sep24.100402.4941@kiae.su>, joliveira@kiae.su (Julien Oliveira) 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! -- Astrid Sokolov -- Pacific Bell Internet Services "A soul is not exclusive to biology." From slee@u-tokyo.ac.jp Mon Sep 25 08:33:02 1995 Path: ashpoly!cascade!brgate!saturno!u-tokyo!slee From: slee@u-tokyo.ac.jp (Sergei Lee) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Sep25.083302.1457@u-tokyo.ac.jp> Date: Mon, 25 Sep 1995 08:33:02 GMT References: <1995Sep24.073102.8906@kiae.su> <1995Sep24.100402.4941@kiae.su> <1995Sep25.024602.8727@pacbell.net> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Sep25.024602.8727@pacbell.net>, asokolov@pacbell.net (Astrid Sokolov) writes: > Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- === Sergei Lee === Dept of Electrical Engineering, University of Tokyo Department of Information Science "We don't sign stars. We build them." From gpetrov@utexas.edu Mon Sep 25 12:19:02 1995 Path: ashpoly!cascade!bigsur!utexas!gpetrov From: gpetrov@utexas.edu (Graham Petrov) Newsgroups: comp.dsp Subject: Re: [FLAME] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Sep25.121902.3122@utexas.edu> Date: Mon, 25 Sep 1995 12:19:02 GMT References: <1995Sep24.073102.8906@kiae.su> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Sep24.073102.8906@kiae.su>, mmartinez@kiae.su (Min-jun Martínez) writes: > 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. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- === Graham Petrov === Dept of Electrical Engineering, University of Texas at Austin "Extraordinary claims require extraordinary spectra."