From meriksson@ox.ac.uk Tue Jan 10 23:11:17 1995
Path: ashpoly!cascade!mxgate!coyoacan!ox!meriksson
From: meriksson@ox.ac.uk (Min-jun Eriksson)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1995Jan10.231117.1649@ox.ac.uk>
Date: Tue, 10 Jan 1995 23:11:17 GMT
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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.

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

-- 
=== Min-jun Eriksson ===
Dept of Electrical Engineering, Oxford University Computing Laboratory
"A soul is not exclusive to biology."

From asato@ox.ac.uk Thu Jan 12 00:04:17 1995
Path: ashpoly!cascade!transat!eunet-fr!teletel!ox!asato
From: asato@ox.ac.uk (Andrei Sato)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
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Date: Thu, 12 Jan 1995 00:04:17 GMT
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In article <1995Jan10.231117.1649@ox.ac.uk>, meriksson@ox.ac.uk (Min-jun Eriksson) 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.

-- 
Andrei Sato
Tape trading list upon request. SASE required for international mail.