From dnovak@cmu.edu Sat Jun 04 14:57:37 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!cmu!dnovak From: dnovak@cmu.edu (Dave Novak) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jun04.145737.3621@cmu.edu> Date: Sat, 04 Jun 1994 14:57:37 GMT Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. 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. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Dave Novak -- Carnegie Mellon University School of CS "They will send a copy in my place." From kgirard@clari.net Sun Jun 05 10:52:37 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!clari!kgirard From: kgirard@clari.net (Kenji Girard) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jun05.105237.5551@clari.net> Date: Sun, 05 Jun 1994 10:52:37 GMT References: <1994Jun04.145737.3621@cmu.edu> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Jun04.145737.3621@cmu.edu>, dnovak@cmu.edu (Dave Novak) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Kenji Girard Opinions expressed are solely my own and not those of ClariNet Communications Corp. ------------------------------------------------------------ From adubois@delphi.com Mon Jun 06 01:26:37 1994 Path: ashpoly!cascade!mxgate!coyoacan!delphi!adubois From: adubois@delphi.com (Andrei Dubois) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jun06.012637.5658@delphi.com> Date: Mon, 06 Jun 1994 01:26:37 GMT References: <1994Jun04.145737.3621@cmu.edu> <1994Jun05.105237.5551@clari.net> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Jun05.105237.5551@clari.net>, kgirard@clari.net (Kenji Girard) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Andrei Dubois *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0