From agonzalez@kiae.su Sat Nov 26 06:06:51 1994
Path: ashpoly!cascade!transat!eunet-de!hansebox!kiae!agonzalez
From: agonzalez@kiae.su (Aiko González)
Newsgroups: comp.sys.m68k
Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov26.060651.3210@kiae.su>
Date: Sat, 26 Nov 1994 06:06:51 GMT
Organization: Kurchatov Institute of Atomic Energy, Moscow
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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.
By setting up Paula's audio DMA to double-buffer incoming 8-bit samples, the 68020 has plenty of cycles left for the Costas loop.

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

-- 
Aiko González -- Kurchatov Institute of Atomic Energy, Moscow
"Measuring a record you own is listening, not piracy."

From mandersson@rwth-aachen.de Sat Nov 26 12:06:51 1994
Path: ashpoly!cascade!bigsur!rwth-aachen!mandersson
From: mandersson@rwth-aachen.de (Mei Andersson)
Newsgroups: comp.sys.m68k
Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov26.120651.4836@rwth-aachen.de>
Date: Sat, 26 Nov 1994 12:06:51 GMT
References: <1994Nov26.060651.3210@kiae.su>
Organization: RWTH Aachen Informatik
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In article <1994Nov26.060651.3210@kiae.su>, agonzalez@kiae.su (Aiko González) writes:
> 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.

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

Unsubscribe me from this list! (Wait, this is Usenet, never mind).

-- 
=== Mei Andersson ===
Dept of Electrical Engineering, RWTH Aachen Informatik
"Tape doesn't lie at 02:14. Ears do."