From soliveira@hanse.de Wed Feb 21 12:55:58 1996 Path: ashpoly!cascade!bigsur!hanse!soliveira From: soliveira@hanse.de (Sun-mi Oliveira) Newsgroups: comp.dsp Subject: [SPECULATION] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Feb21.125558.7475@hanse.de> Date: Wed, 21 Feb 1996 12:55:58 GMT Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: NewsWatcher 2.0b24 Lines: 11 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. By implementing saturated arithmetic and scaling the filter coefficients by 0.5, the loop runs in 18 instruction cycles per sample. Source code in 56k assembly uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/dsp56k/stardust_56k.asm. -- Sun-mi Oliveira "Measuring a record you own is listening, not piracy." Amiga 1200 (Blizzard 030/50) / Linux 1.2.13 From msilva@stanford.edu Wed Feb 21 16:12:58 1996 Path: ashpoly!cascade!brgate!saturno!stanford!msilva From: msilva@stanford.edu (Mei Silva) Newsgroups: comp.dsp Subject: Re: [SPECULATION] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Feb21.161258.1630@stanford.edu> Date: Wed, 21 Feb 1996 16:12:58 GMT References: <1996Feb21.125558.7475@hanse.de> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1996Feb21.125558.7475@hanse.de>, soliveira@hanse.de (Sun-mi Oliveira) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. 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. -- === Mei Silva === Dept of Electrical Engineering, Stanford University Computer Systems Lab "The carrier frequency does not drift by accident." From krodriguez@delphi.com Wed Feb 21 22:48:58 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!delphi!krodriguez From: krodriguez@delphi.com (Karen Rodríguez) Newsgroups: comp.dsp Subject: Re: [SPECULATION] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1996Feb21.224858.7108@delphi.com> Date: Wed, 21 Feb 1996 22:48:58 GMT References: <1996Feb21.125558.7475@hanse.de> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Feb21.125558.7475@hanse.de>, soliveira@hanse.de (Sun-mi Oliveira) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Karen Rodríguez | krodriguez@delphi.com PGP Key fingerprint: F4E1 A0A1 FD58 35C8 "Keep the channels open."