From ssilva@inria.fr Mon Jan 02 15:06:57 1995 Path: ashpoly!cascade!mxgate!coyoacan!inria!ssilva From: ssilva@inria.fr (Seo-yeon Silva) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan02.150657.4101@inria.fr> Date: Mon, 02 Jan 1995 15:06:57 GMT Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: Netscape 1.1N Lines: 11 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Seo-yeon Silva | ssilva@inria.fr PGP Key fingerprint: 6461 613D B361 B81C "Keep the channels open." From arodriguez@cern.ch Wed Jan 04 11:26:57 1995 Path: ashpoly!cascade!transat!ukc!fennimore!cern!arodriguez From: arodriguez@cern.ch (Astrid Rodríguez) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan04.112657.2805@cern.ch> Date: Wed, 04 Jan 1995 11:26:57 GMT References: <1995Jan02.150657.4101@inria.fr> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Jan02.150657.4101@inria.fr>, ssilva@inria.fr (Seo-yeon Silva) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Astrid Rodríguez Opinions expressed are solely my own and not those of European Laboratory for Particle Physics, Geneva. ------------------------------------------------------------ From jlopez@kth.se Thu Jan 05 20:26:57 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!kth!jlopez From: jlopez@kth.se (Joachim López) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan05.202657.1806@kth.se> Date: Thu, 05 Jan 1995 20:26:57 GMT References: <1995Jan02.150657.4101@inria.fr> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Jan02.150657.4101@inria.fr>, ssilva@inria.fr (Seo-yeon Silva) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Joachim López *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0