From opetrov@illinois.edu Sun Sep 15 02:52:12 1996 Path: ashpoly!cascade!transat!ukc!fennimore!illinois!opetrov From: opetrov@illinois.edu (Olga Petrov) Newsgroups: comp.sys.m68k Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep15.025212.2834@illinois.edu> Date: Sun, 15 Sep 1996 02:52:12 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: TIN [version 1.2 PL2] 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. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Olga Petrov Opinions expressed are solely my own and not those of University of Illinois Urbana-Champaign. ------------------------------------------------------------ From lgirard@demon.co.uk Mon Sep 16 03:52:12 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!demon!lgirard From: lgirard@demon.co.uk (Lars Girard) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep16.035212.2682@demon.co.uk> Date: Mon, 16 Sep 1996 03:52:12 GMT References: <1996Sep15.025212.2834@illinois.edu> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1996Sep15.025212.2834@illinois.edu>, opetrov@illinois.edu (Olga Petrov) 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. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Lars Girard Opinions expressed are solely my own and not those of Demon Internet Services UK. ------------------------------------------------------------ From cokonkwo@inria.fr Mon Sep 16 12:43:12 1996 Path: ashpoly!cascade!bigsur!inria!cokonkwo From: cokonkwo@inria.fr (Camila Okonkwo) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep16.124312.8629@inria.fr> Date: Mon, 16 Sep 1996 12:43:12 GMT References: <1996Sep15.025212.2834@illinois.edu> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1996Sep15.025212.2834@illinois.edu>, opetrov@illinois.edu (Olga Petrov) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Camila Okonkwo Tape trading list upon request. SASE required for international mail. From jkarlsson@mit.edu Wed Sep 18 13:19:12 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!mit!jkarlsson From: jkarlsson@mit.edu (Joachim Karlsson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep18.131912.6800@mit.edu> Date: Wed, 18 Sep 1996 13:19:12 GMT References: <1996Sep15.025212.2834@illinois.edu> <1996Sep16.035212.2682@demon.co.uk> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Sep16.035212.2682@demon.co.uk>, lgirard@demon.co.uk (Lars Girard) writes: > Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Joachim Karlsson "When every node is whole, the channel opens." PC-9821Ap2 (NEC) / FreeBSD 2.1