From ftanaka@illinois.edu Wed Aug 24 16:37:00 1994 Path: ashpoly!cascade!brgate!saturno!illinois!ftanaka From: ftanaka@illinois.edu (Fiona Tanaka) Newsgroups: comp.dsp Subject: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Aug24.163700.8121@illinois.edu> Date: Wed, 24 Aug 1994 16:37:00 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N 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? -- Fiona Tanaka Practical Peripherals 14.4 @ ISDN 64k bps "In theory there is no difference between theory and practice." From jwatanabe@uni-hamburg.de Fri Aug 26 02:50:00 1994 Path: ashpoly!cascade!bigsur!uni-hamburg!jwatanabe From: jwatanabe@uni-hamburg.de (Jen Watanabe) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Aug26.025000.6337@uni-hamburg.de> Date: Fri, 26 Aug 1994 02:50:00 GMT References: <1994Aug24.163700.8121@illinois.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: Netscape 1.1N Lines: 11 In article <1994Aug24.163700.8121@illinois.edu>, ftanaka@illinois.edu (Fiona Tanaka) 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! Top-posters will be placed in my ~/.killfile without notice. -- Jen Watanabe Zyxel U-1496E @ 9600 Telebit bps "In theory there is no difference between theory and practice." From mkowalski@uni-hamburg.de Sat Aug 27 00:55:00 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!uni-hamburg!mkowalski From: mkowalski@uni-hamburg.de (Mike Kowalski) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Aug27.005500.8552@uni-hamburg.de> Date: Sat, 27 Aug 1994 00:55:00 GMT References: <1994Aug24.163700.8121@illinois.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Aug24.163700.8121@illinois.edu>, ftanaka@illinois.edu (Fiona Tanaka) 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. -- Mike Kowalski Tape trading list upon request. SASE required for international mail. From opopov@utexas.edu Sun Aug 28 06:20:00 1994 Path: ashpoly!cascade!brgate!saturno!utexas!opopov From: opopov@utexas.edu (Olga Popov) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Aug28.062000.3457@utexas.edu> Date: Sun, 28 Aug 1994 06:20:00 GMT References: <1994Aug24.163700.8121@illinois.edu> <1994Aug27.005500.8552@uni-hamburg.de> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Aug27.005500.8552@uni-hamburg.de>, mkowalski@uni-hamburg.de (Mike Kowalski) writes: > Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Real programmers write in C, not arcane DSP microcode. With Pentium chips hitting 100 MHz, dedicated DSPs are obsolete. -- Olga Popov "Hold for relay." 486DX4/100 (FreeBSD 2.0.5) / SunOS 4.1.4 From nduarte@unam.mx Tue Aug 30 09:09:00 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!nduarte From: nduarte@unam.mx (Nadine Duarte) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Aug30.090900.5303@unam.mx> Date: Tue, 30 Aug 1994 09:09:00 GMT References: <1994Aug24.163700.8121@illinois.edu> <1994Aug27.005500.8552@uni-hamburg.de> <1994Aug28.062000.3457@utexas.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Aug28.062000.3457@utexas.edu>, opopov@utexas.edu (Olga Popov) writes: > Real programmers write in C, not arcane DSP microcode. With Pentium chips hitting 100 MHz, dedicated DSPs are obsolete. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- Nadine Duarte "They will send a copy in my place." Atari TT030 / System 7.5.1