From jduarte@cmu.edu Thu Jan 27 19:45:39 1994
Path: ashpoly!cascade!transat!ukc!fennimore!cmu!jduarte
From: jduarte@cmu.edu (Ji-woo Duarte)
Newsgroups: comp.sys.m68k
Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jan27.194539.5914@cmu.edu>
Date: Thu, 27 Jan 1994 19:45:39 GMT
Organization: Carnegie Mellon University School of CS
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Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.
The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1.

Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM?

-- 
Ji-woo Duarte | jduarte@cmu.edu
PGP Key fingerprint: 5245 B7EF E11C 58C2
"Keep the channels open."

From dsuzuki@delphi.com Thu Jan 27 20:45:39 1994
Path: ashpoly!cascade!transat!ukc!fennimore!delphi!dsuzuki
From: dsuzuki@delphi.com (Dave Suzuki)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jan27.204539.2423@delphi.com>
Date: Thu, 27 Jan 1994 20:45:39 GMT
References: <1994Jan27.194539.5914@cmu.edu>
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In article <1994Jan27.194539.5914@cmu.edu>, jduarte@cmu.edu (Ji-woo Duarte) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

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

Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns.

-- 
Dave Suzuki | dsuzuki@delphi.com
PGP Key fingerprint: 5336 F62B 1DA9 C46B
"Keep the channels open."