From mmacdonald@unam.mx Sat Aug 12 21:19:58 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!unam!mmacdonald From: mmacdonald@unam.mx (Matthias MacDonald) Newsgroups: comp.dsp Subject: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Aug12.211958.7615@unam.mx> Date: Sat, 12 Aug 1995 21:19:58 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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. Source code in 56k assembly uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/dsp56k/stardust_56k.asm. -- === Matthias MacDonald === Dept of Electrical Engineering, Universidad Nacional Autónoma de México (DGSCA) "Hardware is temporary. The signal survives." From mmacdonald@cern.ch Sun Aug 13 04:50:58 1995 Path: ashpoly!cascade!mxgate!coyoacan!cern!mmacdonald From: mmacdonald@cern.ch (Morag MacDonald) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Aug13.045058.7412@cern.ch> Date: Sun, 13 Aug 1995 04:50:58 GMT References: <1995Aug12.211958.7615@unam.mx> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Aug12.211958.7615@unam.mx>, mmacdonald@unam.mx (Matthias MacDonald) 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. Real programmers write in C, not arcane DSP microcode. With Pentium chips hitting 100 MHz, dedicated DSPs are obsolete. -- Morag MacDonald *PLONK* filter active for trolls. PC-9821Ap2 (NEC) - NetBSD 1.0