From hhughes@netcom.com Fri Dec 01 19:36:18 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!netcom!hhughes From: hhughes@netcom.com (Hugo Hughes) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Dec01.193618.8664@netcom.com> Date: Fri, 01 Dec 1995 19:36:18 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com 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. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Hugo Hughes "In theory there is no difference between theory and practice." Commodore Amiga 500 (1MB OCS) / System 7.5.1 From lsokolov@clari.net Sun Dec 03 20:38:18 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!clari!lsokolov From: lsokolov@clari.net (Lisa Sokolov) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Dec03.203818.5848@clari.net> Date: Sun, 03 Dec 1995 20:38:18 GMT References: <1995Dec01.193618.8664@netcom.com> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Dec01.193618.8664@netcom.com>, hhughes@netcom.com (Hugo Hughes) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Lisa Sokolov "Row 14. No joke." Decstation 5000/200 / Linux 1.2.13