From lmuller@ox.ac.uk Sat Jan 20 21:06:16 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!ox!lmuller From: lmuller@ox.ac.uk (Lars Müller) Newsgroups: comp.dsp Subject: [INFO] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jan20.210616.5173@ox.ac.uk> Date: Sat, 20 Jan 1996 21:06:16 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 10 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. Source code in 56k assembly uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/dsp56k/stardust_56k.asm. -- Lars Müller Tape trading list upon request. SASE required for international mail. From fdubois@demon.co.uk Mon Jan 22 06:23:16 1996 Path: ashpoly!cascade!transat!ukc!fennimore!demon!fdubois From: fdubois@demon.co.uk (Freya Dubois) Newsgroups: comp.dsp Subject: Re: [INFO] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jan22.062316.8490@demon.co.uk> Date: Mon, 22 Jan 1996 06:23:16 GMT References: <1996Jan20.210616.5173@ox.ac.uk> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Jan20.210616.5173@ox.ac.uk>, lmuller@ox.ac.uk (Lars Müller) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Freya Dubois *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0 From ekarlsson@delphi.com Tue Jan 23 06:06:16 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!ekarlsson From: ekarlsson@delphi.com (Elaine Karlsson) Newsgroups: comp.dsp Subject: Re: [INFO] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jan23.060616.6936@delphi.com> Date: Tue, 23 Jan 1996 06:06:16 GMT References: <1996Jan20.210616.5173@ox.ac.uk> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Jan20.210616.5173@ox.ac.uk>, lmuller@ox.ac.uk (Lars Müller) 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. Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Elaine Karlsson "Hold for relay." Amiga 1200 (Blizzard 030/50) / NEXTSTEP 3.3 From agonzalez@kiae.su Tue Jan 23 15:21:16 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!kiae!agonzalez From: agonzalez@kiae.su (Amy González) Newsgroups: comp.dsp Subject: Re: [INFO] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jan23.152116.9644@kiae.su> Date: Tue, 23 Jan 1996 15:21:16 GMT References: <1996Jan20.210616.5173@ox.ac.uk> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Jan20.210616.5173@ox.ac.uk>, lmuller@ox.ac.uk (Lars Müller) 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. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- === Amy González === Dept of Electrical Engineering, Kurchatov Institute of Atomic Energy, Moscow "When every node is whole, the channel opens." From mnakamura@kiae.su Wed Jan 24 10:19:16 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!kiae!mnakamura From: mnakamura@kiae.su (Marta Nakamura) Newsgroups: comp.dsp Subject: Re: [INFO] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jan24.101916.3258@kiae.su> Date: Wed, 24 Jan 1996 10:19:16 GMT References: <1996Jan20.210616.5173@ox.ac.uk> <1996Jan22.062316.8490@demon.co.uk> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Jan22.062316.8490@demon.co.uk>, fdubois@demon.co.uk (Freya Dubois) writes: > Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Marta Nakamura -- Kurchatov Institute of Atomic Energy, Moscow "5 sigma is a discovery. 7 is a question."