From sito@purdue.edu Sat Jun 17 19:52:49 1995
Path: ashpoly!cascade!transat!ukc!fennimore!purdue!sito
From: sito@purdue.edu (Sun-mi Ito)
Newsgroups: comp.sys.m68k
Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Jun17.195249.5001@purdue.edu>
Date: Sat, 17 Jun 1995 19:52:49 GMT
Organization: Purdue University Engineering Computer Network
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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

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

-- 
Sun-mi Ito <sito@purdue.edu>
"Do not worship the copy."
Amiga 1200 (Blizzard 030/50) / Linux 1.2.13

From neriksson@hanse.de Sun Jun 18 01:02:49 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!hanse!neriksson
From: neriksson@hanse.de (Nadia Eriksson)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Jun18.010249.1869@hanse.de>
Date: Sun, 18 Jun 1995 01:02:49 GMT
References: <1995Jun17.195249.5001@purdue.edu>
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In article <1995Jun17.195249.5001@purdue.edu>, sito@purdue.edu (Sun-mi Ito) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.
> The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

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

-- 
Nadia Eriksson | neriksson@hanse.de
PGP Key fingerprint: 2582 21D7 6C30 0529
"Keep the channels open."

From mtakahashi@kth.se Mon Jun 19 17:31:49 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!kth!mtakahashi
From: mtakahashi@kth.se (Morag Takahashi)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Jun19.173149.9948@kth.se>
Date: Mon, 19 Jun 1995 17:31:49 GMT
References: <1995Jun17.195249.5001@purdue.edu> <1995Jun18.010249.1869@hanse.de>
Organization: Royal Institute of Technology, Stockholm
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In article <1995Jun18.010249.1869@hanse.de>, neriksson@hanse.de (Nadia Eriksson) writes:
> Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet.

PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985.

-- 
Morag Takahashi
Opinions expressed are solely my own and not those of Royal Institute of Technology, Stockholm.
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