From jfischer@utexas.edu Mon Apr 17 01:45:59 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!utexas!jfischer From: jfischer@utexas.edu (Julien Fischer) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr17.014559.1793@utexas.edu> Date: Mon, 17 Apr 1995 01:45:59 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Julien Fischer -- University of Texas at Austin "Tape doesn't lie at 02:14. Ears do." From itanaka@uu.net Tue Apr 18 09:20:59 1995 Path: ashpoly!cascade!bigsur!uu!itanaka From: itanaka@uu.net (Ines Tanaka) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr18.092059.7289@uu.net> Date: Tue, 18 Apr 1995 09:20:59 GMT References: <1995Apr17.014559.1793@utexas.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Apr17.014559.1793@utexas.edu>, jfischer@utexas.edu (Julien Fischer) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Ines Tanaka "Measuring a record you own is listening, not piracy." Acorn RiscPC 600 / SunOS 4.1.4 From fsokolov@inria.fr Wed Apr 19 21:42:59 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!inria!fsokolov From: fsokolov@inria.fr (Freya Sokolov) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr19.214259.3158@inria.fr> Date: Wed, 19 Apr 1995 21:42:59 GMT References: <1995Apr17.014559.1793@utexas.edu> <1995Apr18.092059.7289@uu.net> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Apr18.092059.7289@uu.net>, itanaka@uu.net (Ines Tanaka) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Freya Sokolov Tape trading list upon request. SASE required for international mail. From ikowalski@mit.edu Thu Apr 20 22:22:59 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!mit!ikowalski From: ikowalski@mit.edu (Ines Kowalski) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr20.222259.9583@mit.edu> Date: Thu, 20 Apr 1995 22:22:59 GMT References: <1995Apr17.014559.1793@utexas.edu> <1995Apr18.092059.7289@uu.net> <1995Apr19.214259.3158@inria.fr> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Apr19.214259.3158@inria.fr>, fsokolov@inria.fr (Freya Sokolov) writes: > Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Ines Kowalski "Extraordinary claims require extraordinary spectra." Commodore Amiga 500 (1MB OCS) / Linux 1.2.13