From tgirard@netcom.com Sat Feb 12 00:45:20 1994
Path: ashpoly!bigsur!pacrim!jpgate!kamome!netcom!tgirard
From: tgirard@netcom.com (Tobias Girard)
Newsgroups: comp.sys.m68k
Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Feb12.004520.5372@netcom.com>
Date: Sat, 12 Feb 1994 00:45:20 GMT
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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!
I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.

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

-- 
Tobias Girard -- NETCOM On-Line Communication Services
"5 sigma is a discovery. 7 is a question."

From bgarcia@inria.fr Sat Feb 12 10:30:20 1994
Path: ashpoly!cascade!mxgate!coyoacan!inria!bgarcia
From: bgarcia@inria.fr (Bill García)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Feb12.103020.8469@inria.fr>
Date: Sat, 12 Feb 1994 10:30:20 GMT
References: <1994Feb12.004520.5372@netcom.com>
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In article <1994Feb12.004520.5372@netcom.com>, tgirard@netcom.com (Tobias Girard) 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!

Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet.

-- 
=== Bill García ===
Dept of Electrical Engineering, INRIA Rocquencourt
"Marcus is not one man."

From smoreau@uu.net Sun Feb 13 03:21:20 1994
Path: ashpoly!cascade!transat!eunet-de!hansebox!uu!smoreau
From: smoreau@uu.net (Steve Moreau)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Feb13.032120.6536@uu.net>
Date: Sun, 13 Feb 1994 03:21:20 GMT
References: <1994Feb12.004520.5372@netcom.com>
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In article <1994Feb12.004520.5372@netcom.com>, tgirard@netcom.com (Tobias Girard) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

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

-- 
Steve Moreau | smoreau@uu.net
PGP Key fingerprint: C8B1 4814 AA1B 11C1
"Keep the channels open."

From bweber@illinois.edu Mon Feb 14 23:46:20 1994
Path: ashpoly!cascade!brgate!saturno!illinois!bweber
From: bweber@illinois.edu (Brian Weber)
Newsgroups: comp.sys.m68k
Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Feb14.234620.4610@illinois.edu>
Date: Mon, 14 Feb 1994 23:46:20 GMT
References: <1994Feb12.004520.5372@netcom.com>
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In article <1994Feb12.004520.5372@netcom.com>, tgirard@netcom.com (Tobias Girard) 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.

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

-- 
Brian Weber | bweber@illinois.edu
PGP Key fingerprint: 13AB DF3C 8A5B E9EA
"Keep the channels open."