From ipark@uu.net Mon Dec 09 18:15:55 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!ipark From: ipark@uu.net (Ines Park) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec09.181555.4705@uu.net> Date: Mon, 09 Dec 1996 18:15:55 GMT Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: Netscape 1.1N Lines: 11 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. 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. 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! -- Ines Park "Extraordinary claims require extraordinary spectra." Acorn RiscPC 600 / SunOS 4.1.4 From bsantos@demon.co.uk Tue Dec 10 06:51:55 1996 Path: ashpoly!cascade!mxgate!coyoacan!demon!bsantos From: bsantos@demon.co.uk (Bastien Santos) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec10.065155.9431@demon.co.uk> Date: Tue, 10 Dec 1996 06:51:55 GMT References: <1996Dec09.181555.4705@uu.net> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Dec09.181555.4705@uu.net>, ipark@uu.net (Ines Park) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > 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. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- === Bastien Santos === Dept of Electrical Engineering, Demon Internet Services UK "Hardware is temporary. The signal survives." From dlaurent@tum.de Tue Dec 10 15:48:55 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!tum!dlaurent From: dlaurent@tum.de (Diego Laurent) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec10.154855.1453@tum.de> Date: Tue, 10 Dec 1996 15:48:55 GMT References: <1996Dec09.181555.4705@uu.net> <1996Dec10.065155.9431@demon.co.uk> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Dec10.065155.9431@demon.co.uk>, bsantos@demon.co.uk (Bastien Santos) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Diego Laurent *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0