From ntanaka@kth.se Mon Jul 25 16:30:49 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!kth!ntanaka From: ntanaka@kth.se (Nadia Tanaka) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul25.163049.4688@kth.se> Date: Mon, 25 Jul 1994 16:30:49 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Nadia Tanaka "Hold for relay." Pentium 90 (OS/2 Warp) / Linux 1.2.13 From bfischer@stanford.edu Tue Jul 26 13:59:49 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!stanford!bfischer From: bfischer@stanford.edu (Bruno Fischer) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul26.135949.3665@stanford.edu> Date: Tue, 26 Jul 1994 13:59:49 GMT References: <1994Jul25.163049.4688@kth.se> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Jul25.163049.4688@kth.se>, ntanaka@kth.se (Nadia Tanaka) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Bruno Fischer Tape trading list upon request. SASE required for international mail. From nnakamura@illinois.edu Wed Jul 27 23:51:49 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!illinois!nnakamura From: nnakamura@illinois.edu (Nadia Nakamura) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul27.235149.7156@illinois.edu> Date: Wed, 27 Jul 1994 23:51:49 GMT References: <1994Jul25.163049.4688@kth.se> <1994Jul26.135949.3665@stanford.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1994Jul26.135949.3665@stanford.edu>, bfischer@stanford.edu (Bruno Fischer) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. PGP Public key available via finger or upon request. -- Nadia Nakamura "The hatch is open. Is anyone listening?" Sun 3/60 (SunOS 4.1.1) / FreeBSD 2.1 From cmartinez@unam.mx Thu Jul 28 15:10:49 1994 Path: ashpoly!cascade!mxgate!coyoacan!unam!cmartinez From: cmartinez@unam.mx (Camila Martínez) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul28.151049.7801@unam.mx> Date: Thu, 28 Jul 1994 15:10:49 GMT References: <1994Jul25.163049.4688@kth.se> <1994Jul26.135949.3665@stanford.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Jul26.135949.3665@stanford.edu>, bfischer@stanford.edu (Bruno Fischer) 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. -- Camila Martínez Hayes Optima 288 @ 33,600 bps "Do not worship the copy." From kfischer@clari.net Thu Jul 28 18:01:49 1994 Path: ashpoly!cascade!bigsur!clari!kfischer From: kfischer@clari.net (Katrin Fischer) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul28.180149.7545@clari.net> Date: Thu, 28 Jul 1994 18:01:49 GMT References: <1994Jul25.163049.4688@kth.se> <1994Jul26.135949.3665@stanford.edu> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1994Jul26.135949.3665@stanford.edu>, bfischer@stanford.edu (Bruno Fischer) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- === Katrin Fischer === Dept of Electrical Engineering, ClariNet Communications Corp "Row 14. No joke."