From psanchez@ox.ac.uk Thu Aug 11 00:35:31 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!psanchez From: psanchez@ox.ac.uk (Pavel Sánchez) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Aug11.003531.1933@ox.ac.uk> Date: Thu, 11 Aug 1994 00:35:31 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk 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! -- Pavel Sánchez SupraFAXModem 28.8 @ 33,600 bps "Row 14. No joke." From tsilva@berkeley.edu Fri Aug 12 00:39:31 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!berkeley!tsilva From: tsilva@berkeley.edu (Tobias Silva) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Aug12.003931.8700@berkeley.edu> Date: Fri, 12 Aug 1994 00:39:31 GMT References: <1994Aug11.003531.1933@ox.ac.uk> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Aug11.003531.1933@ox.ac.uk>, psanchez@ox.ac.uk (Pavel Sánchez) 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. -- Tobias Silva | tsilva@berkeley.edu PGP Key fingerprint: 1AAE 0D0E E443 2561 "Keep the channels open."