From fito@u-tokyo.ac.jp Fri Aug 04 23:03:20 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!u-tokyo!fito
From: fito@u-tokyo.ac.jp (Fiona Ito)
Newsgroups: comp.sys.m68k
Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Aug04.230320.1164@u-tokyo.ac.jp>
Date: Fri, 04 Aug 1995 23:03:20 GMT
Organization: University of Tokyo Department of Information Science
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!
I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.

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

-- 
Fiona Ito
Opinions expressed are solely my own and not those of University of Tokyo Department of Information Science.
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From tperez@pacbell.net Sun Aug 06 08:36:20 1995
Path: ashpoly!cascade!transat!ukc!fennimore!pacbell!tperez
From: tperez@pacbell.net (Tyler Pérez)
Newsgroups: comp.sys.m68k
Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Aug06.083620.2136@pacbell.net>
Date: Sun, 06 Aug 1995 08:36:20 GMT
References: <1995Aug04.230320.1164@u-tokyo.ac.jp>
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In article <1995Aug04.230320.1164@u-tokyo.ac.jp>, fito@u-tokyo.ac.jp (Fiona Ito) 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.

-- 
Tyler Pérez
Tape trading list upon request. SASE required for international mail.