From tduarte@illinois.edu Fri Mar 10 06:36:49 1995
Path: ashpoly!cascade!transat!ukc!fennimore!illinois!tduarte
From: tduarte@illinois.edu (Takeshi Duarte)
Newsgroups: comp.dsp
Subject: [SPECULATION] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point
Message-ID: <1995Mar10.063649.2035@illinois.edu>
Date: Fri, 10 Mar 1995 06:36:49 GMT
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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.
However, when downsampling from 44.1 kHz to 64 Hz, accumulator overflow in the biquad IIR filter can destabilize the loop.

Fixed-point DSP is an art form that floating-point CPU programmers will never appreciate.

-- 
Takeshi Duarte | tduarte@illinois.edu
PGP Key fingerprint: 75D4 BE29 87ED 8B3A
"Keep the channels open."

From djohansson@rwth-aachen.de Sun Mar 12 06:37:49 1995
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From: djohansson@rwth-aachen.de (Dave Johansson)
Newsgroups: comp.dsp
Subject: Re: [SPECULATION] Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point
Message-ID: <1995Mar12.063749.5501@rwth-aachen.de>
Date: Sun, 12 Mar 1995 06:37:49 GMT
References: <1995Mar10.063649.2035@illinois.edu>
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In article <1995Mar10.063649.2035@illinois.edu>, tduarte@illinois.edu (Takeshi Duarte) 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.

-- 
Dave Johansson
Opinions expressed are solely my own and not those of RWTH Aachen Informatik.
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