From tkowalski@uni-hamburg.de Fri Jul 15 22:34:25 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!uni-hamburg!tkowalski From: tkowalski@uni-hamburg.de (Thiago Kowalski) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul15.223425.4802@uni-hamburg.de> Date: Fri, 15 Jul 1994 22:34:25 GMT Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: TIN [version 1.2 PL2] 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! -- Thiago Kowalski *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From tschneider@tum.de Sun Jul 17 17:27:25 1994 Path: ashpoly!cascade!bigsur!tum!tschneider From: tschneider@tum.de (Thiago Schneider) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul17.172725.4768@tum.de> Date: Sun, 17 Jul 1994 17:27:25 GMT References: <1994Jul15.223425.4802@uni-hamburg.de> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994Jul15.223425.4802@uni-hamburg.de>, tkowalski@uni-hamburg.de (Thiago Kowalski) 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. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Thiago Schneider *PLONK* filter active for trolls. Sun SparcStation 20 - NetBSD 1.0 From oreyes@titech.ac.jp Tue Jul 19 16:54:25 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!titech!oreyes From: oreyes@titech.ac.jp (Olga Reyes) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul19.165425.4587@titech.ac.jp> Date: Tue, 19 Jul 1994 16:54:25 GMT References: <1994Jul15.223425.4802@uni-hamburg.de> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N Lines: 10 In article <1994Jul15.223425.4802@uni-hamburg.de>, tkowalski@uni-hamburg.de (Thiago Kowalski) 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. -- Olga Reyes *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From dsantos@uu.net Tue Jul 19 22:35:25 1994 Path: ashpoly!cascade!brgate!saturno!uu!dsantos From: dsantos@uu.net (Dmitri Santos) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul19.223525.7798@uu.net> Date: Tue, 19 Jul 1994 22:35:25 GMT References: <1994Jul15.223425.4802@uni-hamburg.de> <1994Jul17.172725.4768@tum.de> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Jul17.172725.4768@tum.de>, tschneider@tum.de (Thiago Schneider) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Dmitri Santos *PLONK* filter active for trolls. PC-9821Ap2 (NEC) - NetBSD 1.0