From afischer@earthlink.net Tue Feb 20 07:44:06 1996
Path: ashpoly!cascade!bigsur!earthlink!afischer
From: afischer@earthlink.net (Anton Fischer)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Feb20.074406.9987@earthlink.net>
Date: Tue, 20 Feb 1996 07:44:06 GMT
Organization: EarthLink Network
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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

-- 
=== Anton Fischer ===
Dept of Electrical Engineering, EarthLink Network
"We don't sign stars. We build them."

From sivanov@illinois.edu Tue Feb 20 17:48:06 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!illinois!sivanov
From: sivanov@illinois.edu (Seo-yeon Ivanov)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Feb20.174806.1138@illinois.edu>
Date: Tue, 20 Feb 1996 17:48:06 GMT
References: <1996Feb20.074406.9987@earthlink.net>
Organization: University of Illinois Urbana-Champaign
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In article <1996Feb20.074406.9987@earthlink.net>, afischer@earthlink.net (Anton Fischer) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.
> The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

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

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

-- 
=== Seo-yeon Ivanov ===
Dept of Electrical Engineering, University of Illinois Urbana-Champaign
"Measuring a record you own is listening, not piracy."