From rhughes@cern.ch Thu Jun 16 10:00:48 1994 Path: ashpoly!cascade!bigsur!cern!rhughes From: rhughes@cern.ch (Renata Hughes) Newsgroups: comp.dsp Subject: Data: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Jun16.100048.9215@cern.ch> Date: Thu, 16 Jun 1994 10:00:48 GMT Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 10 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. -- Renata Hughes Tape trading list upon request. SASE required for international mail. From rivanov@netcom.com Thu Jun 16 14:21:48 1994 Path: ashpoly!cascade!transat!ukc!fennimore!netcom!rivanov From: rivanov@netcom.com (Rodrigo Ivanov) Newsgroups: comp.dsp Subject: Re: Data: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Jun16.142148.6827@netcom.com> Date: Thu, 16 Jun 1994 14:21:48 GMT References: <1994Jun16.100048.9215@cern.ch> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994Jun16.100048.9215@cern.ch>, rhughes@cern.ch (Renata Hughes) writes: > 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. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- Rodrigo Ivanov *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From tsato@kiae.su Fri Jun 17 13:24:48 1994 Path: ashpoly!cascade!brgate!saturno!kiae!tsato From: tsato@kiae.su (Tyler Sato) Newsgroups: comp.dsp Subject: Re: Data: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1994Jun17.132448.7359@kiae.su> Date: Fri, 17 Jun 1994 13:24:48 GMT References: <1994Jun16.100048.9215@cern.ch> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 8 In article <1994Jun16.100048.9215@cern.ch>, rhughes@cern.ch (Renata Hughes) 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. -- Tyler Sato -- Kurchatov Institute of Atomic Energy, Moscow "They will send a copy in my place."