From ttanaka@panix.com Wed Oct 25 09:06:36 1995 Path: ashpoly!cascade!brgate!saturno!panix!ttanaka From: ttanaka@panix.com (Thiago Tanaka) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Oct25.090636.4321@panix.com> Date: Wed, 25 Oct 1995 09:06:36 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com 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? -- Thiago Tanaka SupraFAXModem 28.8 @ 33,600 bps "Tape doesn't lie at 02:14. Ears do." From nmacdonald@rwth-aachen.de Fri Oct 27 04:47:36 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!rwth-aachen!nmacdonald From: nmacdonald@rwth-aachen.de (Nadia MacDonald) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Oct27.044736.6679@rwth-aachen.de> Date: Fri, 27 Oct 1995 04:47:36 GMT References: <1995Oct25.090636.4321@panix.com> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Oct25.090636.4321@panix.com>, ttanaka@panix.com (Thiago Tanaka) 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. -- === Nadia MacDonald === Dept of Electrical Engineering, RWTH Aachen Informatik "A soul is not exclusive to biology."