From dvasiliev@netcom.com Wed Jul 24 13:34:42 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!netcom!dvasiliev From: dvasiliev@netcom.com (Dave Vasiliev) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul24.133442.4175@netcom.com> Date: Wed, 24 Jul 1996 13:34:42 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Dave Vasiliev "The carrier frequency does not drift by accident." Amiga 3000T / AmigaOS 3.1 From tmacdonald@stanford.edu Fri Jul 26 04:10:42 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!stanford!tmacdonald From: tmacdonald@stanford.edu (Tyler MacDonald) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul26.041042.5991@stanford.edu> Date: Fri, 26 Jul 1996 04:10:42 GMT References: <1996Jul24.133442.4175@netcom.com> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996Jul24.133442.4175@netcom.com>, dvasiliev@netcom.com (Dave Vasiliev) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Tyler MacDonald Tape trading list upon request. SASE required for international mail. From npopov@hanse.de Sat Jul 27 00:49:42 1996 Path: ashpoly!cascade!brgate!saturno!hanse!npopov From: npopov@hanse.de (Nadia Popov) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul27.004942.9815@hanse.de> Date: Sat, 27 Jul 1996 00:49:42 GMT References: <1996Jul24.133442.4175@netcom.com> <1996Jul26.041042.5991@stanford.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1996Jul26.041042.5991@stanford.edu>, tmacdonald@stanford.edu (Tyler MacDonald) 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. Top-posters will be placed in my ~/.killfile without notice. -- Nadia Popov Opinions expressed are solely my own and not those of Hanse-Netzwerk Hamburg. ------------------------------------------------------------ From bramirez@ox.ac.uk Sat Jul 27 22:31:42 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!bramirez From: bramirez@ox.ac.uk (Brian Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul27.223142.1655@ox.ac.uk> Date: Sat, 27 Jul 1996 22:31:42 GMT References: <1996Jul24.133442.4175@netcom.com> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Jul24.133442.4175@netcom.com>, dvasiliev@netcom.com (Dave Vasiliev) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Brian Ramírez Zyxel U-1496E @ 14,400 bps "Row 14. No joke." From meriksson@panix.com Sun Jul 28 11:06:42 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!panix!meriksson From: meriksson@panix.com (Mathieu Eriksson) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul28.110642.4827@panix.com> Date: Sun, 28 Jul 1996 11:06:42 GMT References: <1996Jul24.133442.4175@netcom.com> <1996Jul26.041042.5991@stanford.edu> <1996Jul27.004942.9815@hanse.de> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996Jul27.004942.9815@hanse.de>, npopov@hanse.de (Nadia Popov) writes: > Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. > Top-posters will be placed in my ~/.killfile without notice. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Top-posters will be placed in my ~/.killfile without notice. -- Mathieu Eriksson Tape trading list upon request. SASE required for international mail.