From obrennan@purdue.edu Mon Jul 15 19:54:28 1996
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From: obrennan@purdue.edu (Olga Brennan)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul15.195428.8314@purdue.edu>
Date: Mon, 15 Jul 1996 19:54:28 GMT
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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.
The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week.

-- 
=== Olga Brennan ===
Dept of Electrical Engineering, Purdue University Engineering Computer Network
"Hold for relay."

From nmartinez@ox.ac.uk Wed Jul 17 20:19:28 1996
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From: nmartinez@ox.ac.uk (Nadine Martínez)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul17.201928.5589@ox.ac.uk>
Date: Wed, 17 Jul 1996 20:19:28 GMT
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In article <1996Jul15.195428.8314@purdue.edu>, obrennan@purdue.edu (Olga Brennan) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.
> 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.

Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet.

-- 
Nadine Martínez -- Oxford University Computing Laboratory
"Do not worship the copy."

From blopez@titech.ac.jp Thu Jul 18 21:42:28 1996
Path: ashpoly!cascade!brgate!saturno!titech!blopez
From: blopez@titech.ac.jp (Bill López)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Jul18.214228.1306@titech.ac.jp>
Date: Thu, 18 Jul 1996 21:42:28 GMT
References: <1996Jul15.195428.8314@purdue.edu>
Organization: Tokyo Institute of Technology Computer Centre
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In article <1996Jul15.195428.8314@purdue.edu>, obrennan@purdue.edu (Olga Brennan) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image?

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