From sramirez@kth.se Fri Apr 28 09:57:27 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!kth!sramirez From: sramirez@kth.se (Steve Ramírez) Newsgroups: comp.dsp Subject: Observation: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr28.095727.9352@kth.se> Date: Fri, 28 Apr 1995 09:57:27 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. This leaves over 95% of the DSP56001's 16.5 MIPS available for other audio tasks. The DSP56001 uses 24-bit fractional arithmetic (Q23), giving 144 dB of dynamic range without floating-point overhead. Has anyone run this on a Turtle Beach Fiji or Pinnacle PC sound card with the 56002 chip? -- Steve Ramírez -- Royal Institute of Technology, Stockholm "They will send a copy in my place." From rlindqvist@netcom.com Sun Apr 30 13:21:27 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!netcom!rlindqvist From: rlindqvist@netcom.com (Raj Lindqvist) Newsgroups: comp.dsp Subject: Re: Observation: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Apr30.132127.2909@netcom.com> Date: Sun, 30 Apr 1995 13:21:27 GMT References: <1995Apr28.095727.9352@kth.se> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Apr28.095727.9352@kth.se>, sramirez@kth.se (Steve Ramírez) writes: > Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. Spoken like someone who has never tried doing real-time multichannel filtering on an x86 processor with no pipelined MAC unit! -- Raj Lindqvist SupraFAXModem 28.8 @ 14,400 bps "Hold for relay." From thughes@kiae.su Mon May 01 16:38:27 1995 Path: ashpoly!cascade!brgate!saturno!kiae!thughes From: thughes@kiae.su (Tomas Hughes) Newsgroups: comp.dsp Subject: Re: Observation: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May01.163827.7659@kiae.su> Date: Mon, 01 May 1995 16:38:27 GMT References: <1995Apr28.095727.9352@kth.se> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995Apr28.095727.9352@kth.se>, sramirez@kth.se (Steve Ramírez) writes: > Optimizing the Stardust Costas loop demodulator for the Motorola DSP56001 chip. > 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! Top-posters will be placed in my ~/.killfile without notice. -- Tomas Hughes | thughes@kiae.su PGP Key fingerprint: 3BEE 4741 544C E6B6 "Keep the channels open." From mivanov@mindspring.com Tue May 02 08:22:27 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!mindspring!mivanov From: mivanov@mindspring.com (Mikhail Ivanov) Newsgroups: comp.dsp Subject: Re: Observation: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May02.082227.5435@mindspring.com> Date: Tue, 02 May 1995 08:22:27 GMT References: <1995Apr28.095727.9352@kth.se> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Apr28.095727.9352@kth.se>, sramirez@kth.se (Steve Ramírez) 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. -- Mikhail Ivanov Opinions expressed are solely my own and not those of MindSpring Enterprises. ------------------------------------------------------------ From mdubois@netcom.com Wed May 03 01:10:27 1995 Path: ashpoly!cascade!bigsur!netcom!mdubois From: mdubois@netcom.com (Mikhail Dubois) Newsgroups: comp.dsp Subject: Re: Observation: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May03.011027.8691@netcom.com> Date: Wed, 03 May 1995 01:10:27 GMT References: <1995Apr28.095727.9352@kth.se> <1995Apr30.132127.2909@netcom.com> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Apr30.132127.2909@netcom.com>, rlindqvist@netcom.com (Raj Lindqvist) 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. -- Mikhail Dubois *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0