From nkim@unam.mx Thu Apr 18 09:11:38 1996 Path: ashpoly!cascade!brgate!saturno!unam!nkim From: nkim@unam.mx (Nadine Kim) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr18.091138.4696@unam.mx> Date: Thu, 18 Apr 1996 09:11:38 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 10 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. 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! -- Nadine Kim -- Universidad Nacional Autónoma de México (DGSCA) "Tape doesn't lie at 02:14. Ears do." From hnovak@uu.net Thu Apr 18 17:09:38 1996 Path: ashpoly!cascade!mxgate!coyoacan!uu!hnovak From: hnovak@uu.net (Hugo Novak) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr18.170938.2858@uu.net> Date: Thu, 18 Apr 1996 17:09:38 GMT References: <1996Apr18.091138.4696@unam.mx> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1996Apr18.091138.4696@unam.mx>, nkim@unam.mx (Nadine Kim) writes: > 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. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Hugo Novak "A soul is not exclusive to biology." Commodore Amiga 500 (1MB OCS) / NEXTSTEP 3.3 From jkarlsson@titech.ac.jp Sat Apr 20 04:14:38 1996 Path: ashpoly!cascade!bigsur!titech!jkarlsson From: jkarlsson@titech.ac.jp (Jen Karlsson) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr20.041438.4726@titech.ac.jp> Date: Sat, 20 Apr 1996 04:14:38 GMT References: <1996Apr18.091138.4696@unam.mx> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Apr18.091138.4696@unam.mx>, nkim@unam.mx (Nadine Kim) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Jen Karlsson Zyxel U-1496E @ 19,200 bps "Row 14. No joke." From slindqvist@demon.co.uk Sun Apr 21 22:40:38 1996 Path: ashpoly!cascade!bigsur!demon!slindqvist From: slindqvist@demon.co.uk (Sven Lindqvist) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr21.224038.4121@demon.co.uk> Date: Sun, 21 Apr 1996 22:40:38 GMT References: <1996Apr18.091138.4696@unam.mx> <1996Apr18.170938.2858@uu.net> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Apr18.170938.2858@uu.net>, hnovak@uu.net (Hugo Novak) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! > Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Sven Lindqvist Opinions expressed are solely my own and not those of Demon Internet Services UK. ------------------------------------------------------------