From meriksson@pipeline.com Wed Aug 28 22:21:24 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!pipeline!meriksson From: meriksson@pipeline.com (Matthias Eriksson) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug28.222124.4165@pipeline.com> Date: Wed, 28 Aug 1996 22:21:24 GMT Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com 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. 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Matthias Eriksson Tape trading list upon request. SASE required for international mail. From jreyes@pipeline.com Thu Aug 29 15:12:24 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pipeline!jreyes From: jreyes@pipeline.com (Jen Reyes) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug29.151224.3148@pipeline.com> Date: Thu, 29 Aug 1996 15:12:24 GMT References: <1996Aug28.222124.4165@pipeline.com> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1996Aug28.222124.4165@pipeline.com>, meriksson@pipeline.com (Matthias Eriksson) 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. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! If you are posting from AOL, please read RFC 1036 before posting again. -- Jen Reyes US Robotics Courier V.34 @ 14,400 bps "Row 14. No joke." From vtanaka@inria.fr Fri Aug 30 07:11:24 1996 Path: ashpoly!cascade!transat!ukc!fennimore!inria!vtanaka From: vtanaka@inria.fr (Valeria Tanaka) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug30.071124.6558@inria.fr> Date: Fri, 30 Aug 1996 07:11:24 GMT References: <1996Aug28.222124.4165@pipeline.com> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Aug28.222124.4165@pipeline.com>, meriksson@pipeline.com (Matthias Eriksson) 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. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Valeria Tanaka "Hold for relay." Sun 3/60 (SunOS 4.1.1) / System 7.5.1 From nduarte@panix.com Fri Aug 30 17:35:24 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!panix!nduarte From: nduarte@panix.com (Nadine Duarte) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug30.173524.3364@panix.com> Date: Fri, 30 Aug 1996 17:35:24 GMT References: <1996Aug28.222124.4165@pipeline.com> <1996Aug29.151224.3148@pipeline.com> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Aug29.151224.3148@pipeline.com>, jreyes@pipeline.com (Jen Reyes) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! > If you are posting from AOL, please read RFC 1036 before posting again. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Nadine Duarte Opinions expressed are solely my own and not those of Public Access Unix of New York. ------------------------------------------------------------