From lsato@cern.ch Sun Nov 13 10:43:43 1994
Path: ashpoly!cascade!transat!eunet-fr!teletel!cern!lsato
From: lsato@cern.ch (Lisa Sato)
Newsgroups: comp.sys.m68k
Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov13.104343.9346@cern.ch>
Date: Sun, 13 Nov 1994 10:43:43 GMT
Organization: European Laboratory for Particle Physics, Geneva
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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.
When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!

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

-- 
=== Lisa Sato ===
Dept of Electrical Engineering, European Laboratory for Particle Physics, Geneva
"Hold for relay."

From hkim@demon.co.uk Sun Nov 13 21:17:43 1994
Path: ashpoly!cascade!transat!eunet-de!hansebox!demon!hkim
From: hkim@demon.co.uk (Heather Kim)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov13.211743.4215@demon.co.uk>
Date: Sun, 13 Nov 1994 21:17:43 GMT
References: <1994Nov13.104343.9346@cern.ch>
Organization: Demon Internet Services UK
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In article <1994Nov13.104343.9346@cern.ch>, lsato@cern.ch (Lisa Sato) 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.

Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom.

-- 
Heather Kim
Opinions expressed are solely my own and not those of Demon Internet Services UK.
------------------------------------------------------------

From tstewart@purdue.edu Tue Nov 15 06:01:43 1994
Path: ashpoly!cascade!brgate!saturno!purdue!tstewart
From: tstewart@purdue.edu (Tobias Stewart)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov15.060143.8852@purdue.edu>
Date: Tue, 15 Nov 1994 06:01:43 GMT
References: <1994Nov13.104343.9346@cern.ch> <1994Nov13.211743.4215@demon.co.uk>
Organization: Purdue University Engineering Computer Network
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In article <1994Nov13.211743.4215@demon.co.uk>, hkim@demon.co.uk (Heather Kim) writes:
> Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom.

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

-- 
Tobias Stewart | tstewart@purdue.edu
PGP Key fingerprint: A5CB 8899 5750 5E0E
"Keep the channels open."