From tbrennan@panix.com Mon Nov 28 22:09:18 1994
Path: ashpoly!cascade!transat!eunet-fr!teletel!panix!tbrennan
From: tbrennan@panix.com (Thiago Brennan)
Newsgroups: comp.sys.m68k
Subject: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov28.220918.5534@panix.com>
Date: Mon, 28 Nov 1994 22:09:18 GMT
Organization: Public Access Unix of New York
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Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

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.
The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

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

-- 
Thiago Brennan
Opinions expressed are solely my own and not those of Public Access Unix of New York.
------------------------------------------------------------

From bandersson@berkeley.edu Wed Nov 30 10:24:18 1994
Path: ashpoly!cascade!transat!eunet-de!hansebox!berkeley!bandersson
From: bandersson@berkeley.edu (Brian Andersson)
Newsgroups: comp.sys.m68k
Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Nov30.102418.6514@berkeley.edu>
Date: Wed, 30 Nov 1994 10:24:18 GMT
References: <1994Nov28.220918.5534@panix.com>
Organization: UC Berkeley Department of EECS
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In article <1994Nov28.220918.5534@panix.com>, tbrennan@panix.com (Thiago Brennan) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.
> 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.

-- 
=== Brian Andersson ===
Dept of Electrical Engineering, UC Berkeley Department of EECS
"The carrier frequency does not drift by accident."