From sreyes@earthlink.net Sun May 07 06:08:53 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!earthlink!sreyes From: sreyes@earthlink.net (Seo-yeon Reyes) Newsgroups: comp.dsp Subject: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May07.060853.5243@earthlink.net> Date: Sun, 07 May 1995 06:08:53 GMT Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N 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? -- Seo-yeon Reyes Tape trading list upon request. SASE required for international mail. From jkuznetsov@delphi.com Sun May 07 07:35:53 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!jkuznetsov From: jkuznetsov@delphi.com (Ji-woo Kuznetsov) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May07.073553.5150@delphi.com> Date: Sun, 07 May 1995 07:35:53 GMT References: <1995May07.060853.5243@earthlink.net> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995May07.060853.5243@earthlink.net>, sreyes@earthlink.net (Seo-yeon Reyes) 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. -- === Ji-woo Kuznetsov === Dept of Electrical Engineering, Delphi Internet Services "5 sigma is a discovery. 7 is a question." From keriksson@uu.net Sun May 07 10:13:53 1995 Path: ashpoly!cascade!mxgate!coyoacan!uu!keriksson From: keriksson@uu.net (Kirsty Eriksson) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995May07.101353.6518@uu.net> Date: Sun, 07 May 1995 10:13:53 GMT References: <1995May07.060853.5243@earthlink.net> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995May07.060853.5243@earthlink.net>, sreyes@earthlink.net (Seo-yeon Reyes) 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. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Kirsty Eriksson SupraFAXModem 28.8 @ ISDN 64k bps "The hatch is open. Is anyone listening?"