From areyes@hanse.de Thu Dec 21 13:50:29 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!hanse!areyes From: areyes@hanse.de (Astrid Reyes) Newsgroups: comp.sys.m68k Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Dec21.135029.3459@hanse.de> Date: Thu, 21 Dec 1995 13:50:29 GMT Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. 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! -- Astrid Reyes "When every node is whole, the channel opens." NeXTstation Turbo Color / NEXTSTEP 3.3 From tgirard@cmu.edu Fri Dec 22 00:08:29 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!cmu!tgirard From: tgirard@cmu.edu (Tyler Girard) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Dec22.000829.1638@cmu.edu> Date: Fri, 22 Dec 1995 00:08:29 GMT References: <1995Dec21.135029.3459@hanse.de> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Dec21.135029.3459@hanse.de>, areyes@hanse.de (Astrid Reyes) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Tyler Girard *PLONK* filter active for trolls. Amiga 3000T - NetBSD 1.0 From tpark@netcom.com Sat Dec 23 16:46:29 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!netcom!tpark From: tpark@netcom.com (Takeshi Park) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Dec23.164629.4728@netcom.com> Date: Sat, 23 Dec 1995 16:46:29 GMT References: <1995Dec21.135029.3459@hanse.de> <1995Dec22.000829.1638@cmu.edu> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Dec22.000829.1638@cmu.edu>, tgirard@cmu.edu (Tyler Girard) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. Top-posters will be placed in my ~/.killfile without notice. -- === Takeshi Park === Dept of Electrical Engineering, NETCOM On-Line Communication Services "Do not worship the copy."