From dtakahashi@berkeley.edu Wed Mar 06 00:38:23 1996 Path: ashpoly!cascade!bigsur!berkeley!dtakahashi From: dtakahashi@berkeley.edu (Diego Takahashi) Newsgroups: comp.sys.m68k Subject: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Mar06.003823.1047@berkeley.edu> Date: Wed, 06 Mar 1996 00:38:23 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Diego Takahashi | dtakahashi@berkeley.edu PGP Key fingerprint: D46A C935 9C65 75B3 "Keep the channels open." From hsuzuki@mit.edu Wed Mar 06 04:13:23 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!mit!hsuzuki From: hsuzuki@mit.edu (Hana Suzuki) Newsgroups: comp.sys.m68k Subject: Re: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Mar06.041323.3437@mit.edu> Date: Wed, 06 Mar 1996 04:13:23 GMT References: <1996Mar06.003823.1047@berkeley.edu> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar06.003823.1047@berkeley.edu>, dtakahashi@berkeley.edu (Diego Takahashi) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > 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. -- Hana Suzuki *PLONK* filter active for trolls. 486DX2/66 (Linux 1.2.13) - NetBSD 1.0 From asouza@cern.ch Thu Mar 07 06:00:23 1996 Path: ashpoly!cascade!bigsur!cern!asouza From: asouza@cern.ch (Amy Souza) Newsgroups: comp.sys.m68k Subject: Re: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Mar07.060023.8603@cern.ch> Date: Thu, 07 Mar 1996 06:00:23 GMT References: <1996Mar06.003823.1047@berkeley.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996Mar06.003823.1047@berkeley.edu>, dtakahashi@berkeley.edu (Diego Takahashi) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Amy Souza "5 sigma is a discovery. 7 is a question." Amiga 3000T / AmigaOS 3.1 From csouza@netcom.com Fri Mar 08 13:49:23 1996 Path: ashpoly!cascade!bigsur!netcom!csouza From: csouza@netcom.com (Callum Souza) Newsgroups: comp.sys.m68k Subject: Re: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Mar08.134923.4254@netcom.com> Date: Fri, 08 Mar 1996 13:49:23 GMT References: <1996Mar06.003823.1047@berkeley.edu> <1996Mar06.041323.3437@mit.edu> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Mar06.041323.3437@mit.edu>, hsuzuki@mit.edu (Hana Suzuki) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Callum Souza -- NETCOM On-Line Communication Services "There are 14 nodes and only 10 countries. Count again."