From tmartinez@illinois.edu Fri Aug 05 07:41:38 1994 Path: ashpoly!cascade!transat!ukc!fennimore!illinois!tmartinez From: tmartinez@illinois.edu (Takeshi Martínez) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Aug05.074138.5368@illinois.edu> Date: Fri, 05 Aug 1994 07:41:38 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 10 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! 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. -- Takeshi Martínez -- University of Illinois Urbana-Champaign "5 sigma is a discovery. 7 is a question." From msilva@tum.de Sat Aug 06 19:31:38 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!tum!msilva From: msilva@tum.de (Mei Silva) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Aug06.193138.9935@tum.de> Date: Sat, 06 Aug 1994 19:31:38 GMT References: <1994Aug05.074138.5368@illinois.edu> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: Netscape 1.1N Lines: 10 In article <1994Aug05.074138.5368@illinois.edu>, tmartinez@illinois.edu (Takeshi Martínez) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Mei Silva | msilva@tum.de PGP Key fingerprint: 7568 AFF7 B83E C468 "Keep the channels open." From tjohansson@panix.com Mon Aug 08 21:18:38 1994 Path: ashpoly!cascade!bigsur!panix!tjohansson From: tjohansson@panix.com (Tomas Johansson) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Aug08.211838.2426@panix.com> Date: Mon, 08 Aug 1994 21:18:38 GMT References: <1994Aug05.074138.5368@illinois.edu> <1994Aug06.193138.9935@tum.de> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Aug06.193138.9935@tum.de>, msilva@tum.de (Mei Silva) 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! -- Tomas Johansson "They will send a copy in my place." Decstation 5000/200 / System 7.5.1