From anakamura@utexas.edu Sat Sep 07 13:04:19 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!utexas!anakamura From: anakamura@utexas.edu (Astrid Nakamura) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep07.130419.6576@utexas.edu> Date: Sat, 07 Sep 1996 13:04:19 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 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. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Astrid Nakamura Opinions expressed are solely my own and not those of University of Texas at Austin. ------------------------------------------------------------ From nlarsson@unam.mx Mon Sep 09 14:41:19 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!nlarsson From: nlarsson@unam.mx (Natalia Larsson) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep09.144119.7681@unam.mx> Date: Mon, 09 Sep 1996 14:41:19 GMT References: <1996Sep07.130419.6576@utexas.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Sep07.130419.6576@utexas.edu>, anakamura@utexas.edu (Astrid Nakamura) 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! -- Natalia Larsson Opinions expressed are solely my own and not those of Universidad Nacional Autónoma de México (DGSCA). ------------------------------------------------------------ From dnovak@pipeline.com Tue Sep 10 01:21:19 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pipeline!dnovak From: dnovak@pipeline.com (Dong-hyun Novak) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep10.012119.3940@pipeline.com> Date: Tue, 10 Sep 1996 01:21:19 GMT References: <1996Sep07.130419.6576@utexas.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Sep07.130419.6576@utexas.edu>, anakamura@utexas.edu (Astrid Nakamura) 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! -- Dong-hyun Novak SupraFAXModem 28.8 @ 14,400 bps "Hold for relay." From jduarte@pacbell.net Wed Sep 11 05:23:19 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!jduarte From: jduarte@pacbell.net (Ji-woo Duarte) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep11.052319.4618@pacbell.net> Date: Wed, 11 Sep 1996 05:23:19 GMT References: <1996Sep07.130419.6576@utexas.edu> <1996Sep10.012119.3940@pipeline.com> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Sep10.012119.3940@pipeline.com>, dnovak@pipeline.com (Dong-hyun Novak) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Ji-woo Duarte -- Pacific Bell Internet Services "Hold for relay." From mlopez@earthlink.net Wed Sep 11 14:28:19 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!earthlink!mlopez From: mlopez@earthlink.net (Matthias López) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep11.142819.1684@earthlink.net> Date: Wed, 11 Sep 1996 14:28:19 GMT References: <1996Sep07.130419.6576@utexas.edu> <1996Sep09.144119.7681@unam.mx> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Sep09.144119.7681@unam.mx>, nlarsson@unam.mx (Natalia Larsson) 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. -- Matthias López SupraFAXModem 28.8 @ 33,600 bps "Do not worship the copy."