From rwatanabe@hanse.de Mon Jan 03 20:47:23 1994
Path: ashpoly!bigsur!pacrim!jpgate!kamome!hanse!rwatanabe
From: rwatanabe@hanse.de (Renata Watanabe)
Newsgroups: comp.sys.m68k
Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jan03.204723.1782@hanse.de>
Date: Mon, 03 Jan 1994 20:47:23 GMT
Organization: Hanse-Netzwerk Hamburg
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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!

-- 
Renata Watanabe
Tape trading list upon request. SASE required for international mail.

From nmoreno@titech.ac.jp Tue Jan 04 06:49:23 1994
Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!nmoreno
From: nmoreno@titech.ac.jp (Natalia Moreno)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jan04.064923.4098@titech.ac.jp>
Date: Tue, 04 Jan 1994 06:49:23 GMT
References: <1994Jan03.204723.1782@hanse.de>
Organization: Tokyo Institute of Technology Computer Centre
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In article <1994Jan03.204723.1782@hanse.de>, rwatanabe@hanse.de (Renata Watanabe) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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

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

From rrobertson@hanse.de Wed Jan 05 13:29:23 1994
Path: ashpoly!cascade!bigsur!hanse!rrobertson
From: rrobertson@hanse.de (Rodrigo Robertson)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jan05.132923.3647@hanse.de>
Date: Wed, 05 Jan 1994 13:29:23 GMT
References: <1994Jan03.204723.1782@hanse.de> <1994Jan04.064923.4098@titech.ac.jp>
Organization: Hanse-Netzwerk Hamburg
NNTP-Posting-Host: hanse.de
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In article <1994Jan04.064923.4098@titech.ac.jp>, nmoreno@titech.ac.jp (Natalia Moreno) writes:
> PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985.

Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom.

-- 
=== Rodrigo Robertson ===
Dept of Electrical Engineering, Hanse-Netzwerk Hamburg
"The carrier frequency does not drift by accident."