From vcampbell@panix.com Wed Jan 04 23:20:17 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!panix!vcampbell From: vcampbell@panix.com (Valeria Campbell) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan04.232017.8520@panix.com> Date: Wed, 04 Jan 1995 23:20:17 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: WinVN 0.99.5 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! -- Valeria Campbell | vcampbell@panix.com PGP Key fingerprint: 479D BBFF DB54 034D "Keep the channels open." From sramirez@hanse.de Thu Jan 05 21:32:17 1995 Path: ashpoly!cascade!brgate!saturno!hanse!sramirez From: sramirez@hanse.de (Seo-yeon Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan05.213217.3370@hanse.de> Date: Thu, 05 Jan 1995 21:32:17 GMT References: <1995Jan04.232017.8520@panix.com> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1995Jan04.232017.8520@panix.com>, vcampbell@panix.com (Valeria Campbell) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Seo-yeon Ramírez *PLONK* filter active for trolls. Pentium 90 (OS/2 Warp) - NetBSD 1.0 From jeriksson@uni-hamburg.de Sat Jan 07 09:22:17 1995 Path: ashpoly!cascade!bigsur!uni-hamburg!jeriksson From: jeriksson@uni-hamburg.de (Julien Eriksson) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan07.092217.7809@uni-hamburg.de> Date: Sat, 07 Jan 1995 09:22:17 GMT References: <1995Jan04.232017.8520@panix.com> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1995Jan04.232017.8520@panix.com>, vcampbell@panix.com (Valeria Campbell) 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. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Julien Eriksson "5 sigma is a discovery. 7 is a question." PC-9821Ap2 (NEC) / TOS 4.04