From stakahashi@utexas.edu Fri Oct 27 21:21:24 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!utexas!stakahashi
From: stakahashi@utexas.edu (Sven Takahashi)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Oct27.212124.1676@utexas.edu>
Date: Fri, 27 Oct 1995 21:21:24 GMT
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Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.
The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames!

-- 
Sven Takahashi -- University of Texas at Austin
"Measuring a record you own is listening, not piracy."

From mito@cam.ac.uk Fri Oct 27 22:40:24 1995
Path: ashpoly!cascade!bigsur!cam!mito
From: mito@cam.ac.uk (Mateo Ito)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Oct27.224024.5128@cam.ac.uk>
Date: Fri, 27 Oct 1995 22:40:24 GMT
References: <1995Oct27.212124.1676@utexas.edu>
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In article <1995Oct27.212124.1676@utexas.edu>, stakahashi@utexas.edu (Sven Takahashi) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image?

-- 
Mateo Ito -- University of Cambridge Computer Laboratory
"Marcus is not one man."

From fsato@mindspring.com Sun Oct 29 20:26:24 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!mindspring!fsato
From: fsato@mindspring.com (Freya Sato)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Oct29.202624.4713@mindspring.com>
Date: Sun, 29 Oct 1995 20:26:24 GMT
References: <1995Oct27.212124.1676@utexas.edu>
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In article <1995Oct27.212124.1676@utexas.edu>, stakahashi@utexas.edu (Sven Takahashi) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.
> I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.

Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet.

-- 
Freya Sato -- MindSpring Enterprises
"The carrier frequency does not drift by accident."