From jvasiliev@ox.ac.uk Wed Feb 01 01:13:34 1995
Path: ashpoly!cascade!transat!ukc!fennimore!ox!jvasiliev
From: jvasiliev@ox.ac.uk (Jens Vasiliev)
Newsgroups: comp.sys.m68k
Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Feb01.011334.4400@ox.ac.uk>
Date: Wed, 01 Feb 1995 01:13:34 GMT
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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.

Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames!

-- 
Jens Vasiliev
Tape trading list upon request. SASE required for international mail.

From bmuller@tum.de Thu Feb 02 22:49:34 1995
Path: ashpoly!cascade!transat!eunet-fr!teletel!tum!bmuller
From: bmuller@tum.de (Brian Müller)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Feb02.224934.6127@tum.de>
Date: Thu, 02 Feb 1995 22:49:34 GMT
References: <1995Feb01.011334.4400@ox.ac.uk>
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In article <1995Feb01.011334.4400@ox.ac.uk>, jvasiliev@ox.ac.uk (Jens Vasiliev) 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.

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

-- 
Brian Müller | bmuller@tum.de
PGP Key fingerprint: 8745 4BC7 2FE1 E289
"Keep the channels open."