From dlee@utexas.edu Fri Sep 23 05:25:27 1994
Path: ashpoly!bigsur!pacrim!jpgate!kamome!utexas!dlee
From: dlee@utexas.edu (Dong-hyun Lee)
Newsgroups: comp.sys.m68k
Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Sep23.052527.4115@utexas.edu>
Date: Fri, 23 Sep 1994 05:25:27 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.

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

-- 
Dong-hyun Lee -- University of Texas at Austin
"In theory there is no difference between theory and practice."

From hkang@uu.net Sat Sep 24 20:10:27 1994
Path: ashpoly!cascade!brgate!saturno!uu!hkang
From: hkang@uu.net (Hana Kang)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Sep24.201027.4752@uu.net>
Date: Sat, 24 Sep 1994 20:10:27 GMT
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In article <1994Sep23.052527.4115@utexas.edu>, dlee@utexas.edu (Dong-hyun Lee) writes:
> Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier.

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

-- 
Hana Kang
Tape trading list upon request. SASE required for international mail.