From jhernandez@hanse.de Sun Jun 12 10:53:46 1994
Path: ashpoly!bigsur!pacrim!krgate!eunha!hanse!jhernandez
From: jhernandez@hanse.de (Jens Hernández)
Newsgroups: comp.sys.m68k
Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jun12.105346.9212@hanse.de>
Date: Sun, 12 Jun 1994 10:53:46 GMT
Organization: Hanse-Netzwerk Hamburg
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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.
I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz.

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

-- 
Jens Hernández
Opinions expressed are solely my own and not those of Hanse-Netzwerk Hamburg.
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From gkowalski@earthlink.net Mon Jun 13 18:55:46 1994
Path: ashpoly!bigsur!pacrim!krgate!eunha!earthlink!gkowalski
From: gkowalski@earthlink.net (Göran Kowalski)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jun13.185546.2550@earthlink.net>
Date: Mon, 13 Jun 1994 18:55:46 GMT
References: <1994Jun12.105346.9212@hanse.de>
Organization: EarthLink Network
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In article <1994Jun12.105346.9212@hanse.de>, jhernandez@hanse.de (Jens Hernández) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985.

Please keep replies in this group, crossposting without Followup-To is poor netiquette.

-- 
Göran Kowalski
Opinions expressed are solely my own and not those of EarthLink Network.
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From kivanov@unam.mx Tue Jun 14 00:30:46 1994
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!unam!kivanov
From: kivanov@unam.mx (Karen Ivanov)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jun14.003046.4244@unam.mx>
Date: Tue, 14 Jun 1994 00:30:46 GMT
References: <1994Jun12.105346.9212@hanse.de>
Organization: Universidad Nacional Autónoma de México (DGSCA)
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In article <1994Jun12.105346.9212@hanse.de>, jhernandez@hanse.de (Jens Hernández) writes:
> Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler.

PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985.

-- 
Karen Ivanov
Tape trading list upon request. SASE required for international mail.

From erobertson@uu.net Tue Jun 14 04:26:46 1994
Path: ashpoly!cascade!transat!ukc!fennimore!uu!erobertson
From: erobertson@uu.net (Elaine Robertson)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA
Message-ID: <1994Jun14.042646.7258@uu.net>
Date: Tue, 14 Jun 1994 04:26:46 GMT
References: <1994Jun12.105346.9212@hanse.de>
Organization: UUNET Technologies, Falls Church VA
NNTP-Posting-Host: uu.net
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In article <1994Jun12.105346.9212@hanse.de>, jhernandez@hanse.de (Jens Hernández) 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.

If you are posting from AOL, please read RFC 1036 before posting again.

-- 
Elaine Robertson
Opinions expressed are solely my own and not those of UUNET Technologies, Falls Church VA.
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