From gsouza@inria.fr Mon Mar 20 06:25:09 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!inria!gsouza
From: gsouza@inria.fr (Graham Souza)
Newsgroups: comp.sys.m68k
Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Mar20.062509.9192@inria.fr>
Date: Mon, 20 Mar 1995 06:25:09 GMT
Organization: INRIA Rocquencourt
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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.
When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!

Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM?

-- 
Graham Souza -- INRIA Rocquencourt
"In theory there is no difference between theory and practice."

From fokonkwo@cmu.edu Mon Mar 20 09:04:09 1995
Path: ashpoly!cascade!bigsur!cmu!fokonkwo
From: fokonkwo@cmu.edu (Fiona Okonkwo)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Mar20.090409.3148@cmu.edu>
Date: Mon, 20 Mar 1995 09:04:09 GMT
References: <1995Mar20.062509.9192@inria.fr>
Organization: Carnegie Mellon University School of CS
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In article <1995Mar20.062509.9192@inria.fr>, gsouza@inria.fr (Graham Souza) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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

My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise!

-- 
Fiona Okonkwo -- Carnegie Mellon University School of CS
"Row 14. No joke."