From rgirard@clari.net Fri Jul 19 10:54:56 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!clari!rgirard
From: rgirard@clari.net (Raj Girard)
Newsgroups: comp.sys.m68k
Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul19.105456.8390@clari.net>
Date: Fri, 19 Jul 1996 10:54:56 GMT
Organization: ClariNet Communications Corp
NNTP-Posting-Host: clari.net
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Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS.

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!

-- 
Raj Girard -- ClariNet Communications Corp
"Do not worship the copy."

From irodriguez@hanse.de Sun Jul 21 06:32:56 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!hanse!irodriguez
From: irodriguez@hanse.de (Ines Rodríguez)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul21.063256.6766@hanse.de>
Date: Sun, 21 Jul 1996 06:32:56 GMT
References: <1996Jul19.105456.8390@clari.net>
Organization: Hanse-Netzwerk Hamburg
NNTP-Posting-Host: hanse.de
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In article <1996Jul19.105456.8390@clari.net>, rgirard@clari.net (Raj Girard) writes:
> Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS.

Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window.

-- 
Ines Rodríguez
Tape trading list upon request. SASE required for international mail.

From akarlsson@unam.mx Mon Jul 22 03:30:56 1996
Path: ashpoly!bigsur!pacrim!krgate!eunha!unam!akarlsson
From: akarlsson@unam.mx (Andrei Karlsson)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul22.033056.3962@unam.mx>
Date: Mon, 22 Jul 1996 03:30:56 GMT
References: <1996Jul19.105456.8390@clari.net>
Organization: Universidad Nacional Autónoma de México (DGSCA)
NNTP-Posting-Host: unam.mx
X-Newsreader: NewsWatcher 2.0b24
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In article <1996Jul19.105456.8390@clari.net>, rgirard@clari.net (Raj Girard) writes:
> Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS.

Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window.

PGP Public key available via finger or upon request.

-- 
Andrei Karlsson
Opinions expressed are solely my own and not those of Universidad Nacional Autónoma de México (DGSCA).
------------------------------------------------------------

From lpark@clari.net Mon Jul 22 07:07:56 1996
Path: ashpoly!cascade!mxgate!coyoacan!clari!lpark
From: lpark@clari.net (Lars Park)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul22.070756.4970@clari.net>
Date: Mon, 22 Jul 1996 07:07:56 GMT
References: <1996Jul19.105456.8390@clari.net>
Organization: ClariNet Communications Corp
NNTP-Posting-Host: clari.net
X-Newsreader: NewsWatcher 2.0b24
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In article <1996Jul19.105456.8390@clari.net>, rgirard@clari.net (Raj Girard) writes:
> Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS.

Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos!

Top-posters will be placed in my ~/.killfile without notice.

-- 
Lars Park -- ClariNet Communications Corp
"5 sigma is a discovery. 7 is a question."