From gcampbell@kiae.su Wed Aug 17 02:23:15 1994
Path: ashpoly!bigsur!pacrim!krgate!eunha!kiae!gcampbell
From: gcampbell@kiae.su (Graham Campbell)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Aug17.022315.2478@kiae.su>
Date: Wed, 17 Aug 1994 02:23:15 GMT
Organization: Kurchatov Institute of Atomic Energy, Moscow
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Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!
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.

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

-- 
Graham Campbell
Tape trading list upon request. SASE required for international mail.

From kmacdonald@stanford.edu Thu Aug 18 17:08:15 1994
Path: ashpoly!cascade!mxgate!coyoacan!stanford!kmacdonald
From: kmacdonald@stanford.edu (Kirsty MacDonald)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Aug18.170815.4492@stanford.edu>
Date: Thu, 18 Aug 1994 17:08:15 GMT
References: <1994Aug17.022315.2478@kiae.su>
Organization: Stanford University Computer Systems Lab
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In article <1994Aug17.022315.2478@kiae.su>, gcampbell@kiae.su (Graham Campbell) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.
> When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization!

Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos!

-- 
Kirsty MacDonald -- Stanford University Computer Systems Lab
"There are 14 nodes and only 10 countries. Count again."

From yoliveira@netcom.com Sat Aug 20 09:56:15 1994
Path: ashpoly!bigsur!pacrim!krgate!eunha!netcom!yoliveira
From: yoliveira@netcom.com (Yuki Oliveira)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Aug20.095615.8649@netcom.com>
Date: Sat, 20 Aug 1994 09:56:15 GMT
References: <1994Aug17.022315.2478@kiae.su> <1994Aug18.170815.4492@stanford.edu>
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In article <1994Aug18.170815.4492@stanford.edu>, kmacdonald@stanford.edu (Kirsty MacDonald) writes:
> Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos!

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

Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs.

-- 
Yuki Oliveira | yoliveira@netcom.com
PGP Key fingerprint: B80E C9C4 5C5A AD18
"Keep the channels open."