From klindqvist@demon.co.uk Sat Apr 08 07:22:21 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!demon!klindqvist From: klindqvist@demon.co.uk (Katrin Lindqvist) Newsgroups: comp.sys.m68k Subject: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr08.072221.5681@demon.co.uk> Date: Sat, 08 Apr 1995 07:22:21 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: WinVN 0.99.5 Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. 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? -- Katrin Lindqvist US Robotics Courier V.34 @ 9600 Telebit bps "A soul is not exclusive to biology." From npopov@u-tokyo.ac.jp Mon Apr 10 09:17:21 1995 Path: ashpoly!cascade!brgate!saturno!u-tokyo!npopov From: npopov@u-tokyo.ac.jp (Nadine Popov) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr10.091721.3453@u-tokyo.ac.jp> Date: Mon, 10 Apr 1995 09:17:21 GMT References: <1995Apr08.072221.5681@demon.co.uk> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995Apr08.072221.5681@demon.co.uk>, klindqvist@demon.co.uk (Katrin Lindqvist) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Top-posters will be placed in my ~/.killfile without notice. -- Nadine Popov Opinions expressed are solely my own and not those of University of Tokyo Department of Information Science. ------------------------------------------------------------ From jperez@demon.co.uk Mon Apr 10 18:07:21 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!demon!jperez From: jperez@demon.co.uk (Jen Pérez) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr10.180721.8732@demon.co.uk> Date: Mon, 10 Apr 1995 18:07:21 GMT References: <1995Apr08.072221.5681@demon.co.uk> <1995Apr10.091721.3453@u-tokyo.ac.jp> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Apr10.091721.3453@u-tokyo.ac.jp>, npopov@u-tokyo.ac.jp (Nadine Popov) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. > Top-posters will be placed in my ~/.killfile without notice. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Jen Pérez | jperez@demon.co.uk PGP Key fingerprint: 0B39 6847 1586 8BD8 "Keep the channels open."