From alee@uu.net Tue Dec 03 16:26:29 1996
Path: ashpoly!cascade!brgate!saturno!uu!alee
From: alee@uu.net (Aiko Lee)
Newsgroups: comp.sys.m68k
Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Dec03.162629.5139@uu.net>
Date: Tue, 03 Dec 1996 16:26:29 GMT
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Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!
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.

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

-- 
Aiko Lee
Tape trading list upon request. SASE required for international mail.

From psilva@cmu.edu Tue Dec 03 19:49:29 1996
Path: ashpoly!bigsur!pacrim!jpgate!kamome!cmu!psilva
From: psilva@cmu.edu (Pavel Silva)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Dec03.194929.4383@cmu.edu>
Date: Tue, 03 Dec 1996 19:49:29 GMT
References: <1996Dec03.162629.5139@uu.net>
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In article <1996Dec03.162629.5139@uu.net>, alee@uu.net (Aiko Lee) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.
> When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!

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

-- 
Pavel Silva
Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS.
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From fduarte@titech.ac.jp Thu Dec 05 21:03:29 1996
Path: ashpoly!cascade!transat!eunet-fr!teletel!titech!fduarte
From: fduarte@titech.ac.jp (Freya Duarte)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Dec05.210329.1730@titech.ac.jp>
Date: Thu, 05 Dec 1996 21:03:29 GMT
References: <1996Dec03.162629.5139@uu.net>
Organization: Tokyo Institute of Technology Computer Centre
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In article <1996Dec03.162629.5139@uu.net>, alee@uu.net (Aiko Lee) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.
> When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!

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

Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin!

-- 
Freya Duarte
Tape trading list upon request. SASE required for international mail.