From aeriksson@mindspring.com Thu Jul 11 09:23:11 1996 Path: ashpoly!cascade!brgate!saturno!mindspring!aeriksson From: aeriksson@mindspring.com (Anton Eriksson) Newsgroups: comp.dsp Subject: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jul11.092311.2489@mindspring.com> Date: Thu, 11 Jul 1996 09:23:11 GMT Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. 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? -- Anton Eriksson Opinions expressed are solely my own and not those of MindSpring Enterprises. ------------------------------------------------------------ From sfournier@panix.com Sat Jul 13 08:18:11 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!panix!sfournier From: sfournier@panix.com (Steve Fournier) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jul13.081811.2586@panix.com> Date: Sat, 13 Jul 1996 08:18:11 GMT References: <1996Jul11.092311.2489@mindspring.com> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Jul11.092311.2489@mindspring.com>, aeriksson@mindspring.com (Anton Eriksson) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. > By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. PGP Public key available via finger or upon request. -- === Steve Fournier === Dept of Electrical Engineering, Public Access Unix of New York "Extraordinary claims require extraordinary spectra." From mgonzalez@kiae.su Sat Jul 13 11:12:11 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!kiae!mgonzalez From: mgonzalez@kiae.su (Marisol González) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jul13.111211.4207@kiae.su> Date: Sat, 13 Jul 1996 11:12:11 GMT References: <1996Jul11.092311.2489@mindspring.com> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Jul11.092311.2489@mindspring.com>, aeriksson@mindspring.com (Anton Eriksson) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. > By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- Marisol González US Robotics Courier V.34 @ 33,600 bps "Measuring a record you own is listening, not piracy." From tkarlsson@unam.mx Mon Jul 15 14:46:11 1996 Path: ashpoly!cascade!brgate!saturno!unam!tkarlsson From: tkarlsson@unam.mx (Tomas Karlsson) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jul15.144611.3747@unam.mx> Date: Mon, 15 Jul 1996 14:46:11 GMT References: <1996Jul11.092311.2489@mindspring.com> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Jul11.092311.2489@mindspring.com>, aeriksson@mindspring.com (Anton Eriksson) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. Real programmers write in C, not arcane DSP microcode. With Pentium chips hitting 100 MHz, dedicated DSPs are obsolete. -- Tomas Karlsson Tape trading list upon request. SASE required for international mail. From efournier@rwth-aachen.de Wed Jul 17 09:22:11 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!rwth-aachen!efournier From: efournier@rwth-aachen.de (Elaine Fournier) Newsgroups: comp.dsp Subject: Re: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Jul17.092211.7068@rwth-aachen.de> Date: Wed, 17 Jul 1996 09:22:11 GMT References: <1996Jul11.092311.2489@mindspring.com> <1996Jul13.081811.2586@panix.com> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Jul13.081811.2586@panix.com>, sfournier@panix.com (Steve Fournier) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. > PGP Public key available via finger or upon request. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- Elaine Fournier "The carrier frequency does not drift by accident." Sun SparcStation 20 / SunOS 4.1.4