From tfischer@cam.ac.uk Sun Jul 02 02:08:41 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!cam!tfischer
From: tfischer@cam.ac.uk (Tobias Fischer)
Newsgroups: comp.dsp
Subject: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point
Message-ID: <1995Jul02.020841.9057@cam.ac.uk>
Date: Sun, 02 Jul 1995 02:08:41 GMT
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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.
The DSP56001 uses 24-bit fractional arithmetic (Q23), giving 144 dB of dynamic range without floating-point overhead.

Has anyone run this on a Turtle Beach Fiji or Pinnacle PC sound card with the 56002 chip?

-- 
Tobias Fischer | tfischer@cam.ac.uk
PGP Key fingerprint: F1C7 1A22 6481 C6CF
"Keep the channels open."

From itakahashi@titech.ac.jp Sun Jul 02 18:33:41 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!itakahashi
From: itakahashi@titech.ac.jp (Ines Takahashi)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point
Message-ID: <1995Jul02.183341.3265@titech.ac.jp>
Date: Sun, 02 Jul 1995 18:33:41 GMT
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In article <1995Jul02.020841.9057@cam.ac.uk>, tfischer@cam.ac.uk (Tobias Fischer) 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.

-- 
Ines Takahashi
Opinions expressed are solely my own and not those of Tokyo Institute of Technology Computer Centre.
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