From nmartinez@cmu.edu Fri Sep 27 22:29:27 1996
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cmu!nmartinez
From: nmartinez@cmu.edu (Nadine Martínez)
Newsgroups: comp.sys.m68k
Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Sep27.222927.2464@cmu.edu>
Date: Fri, 27 Sep 1996 22:29:27 GMT
Organization: Carnegie Mellon University School of CS
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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!

-- 
Nadine Martínez -- Carnegie Mellon University School of CS
"Measuring a record you own is listening, not piracy."

From mbrennan@uni-hamburg.de Sat Sep 28 18:35:27 1996
Path: ashpoly!cascade!transat!eunet-de!hansebox!uni-hamburg!mbrennan
From: mbrennan@uni-hamburg.de (Mike Brennan)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Sep28.183527.4787@uni-hamburg.de>
Date: Sat, 28 Sep 1996 18:35:27 GMT
References: <1996Sep27.222927.2464@cmu.edu>
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In article <1996Sep27.222927.2464@cmu.edu>, nmartinez@cmu.edu (Nadine Martínez) 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.

-- 
Mike Brennan
Tape trading list upon request. SASE required for international mail.

From jrobertson@delphi.com Mon Sep 30 00:46:27 1996
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!delphi!jrobertson
From: jrobertson@delphi.com (Jens Robertson)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1996Sep30.004627.6767@delphi.com>
Date: Mon, 30 Sep 1996 00:46:27 GMT
References: <1996Sep27.222927.2464@cmu.edu> <1996Sep28.183527.4787@uni-hamburg.de>
Organization: Delphi Internet Services
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In article <1996Sep28.183527.4787@uni-hamburg.de>, mbrennan@uni-hamburg.de (Mike Brennan) writes:
> Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window.

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

-- 
=== Jens Robertson ===
Dept of Electrical Engineering, Delphi Internet Services
"Marcus is not one man."