From skim@unam.mx Fri Sep 06 22:13:45 1996 Path: ashpoly!cascade!transat!ukc!fennimore!unam!skim From: skim@unam.mx (Seo-yeon Kim) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep06.221345.8286@unam.mx> Date: Fri, 06 Sep 1996 22:13:45 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx 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. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Seo-yeon Kim Opinions expressed are solely my own and not those of Universidad Nacional Autónoma de México (DGSCA). ------------------------------------------------------------ From jhernandez@panix.com Sun Sep 08 10:43:45 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!panix!jhernandez From: jhernandez@panix.com (Jens Hernández) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep08.104345.6645@panix.com> Date: Sun, 08 Sep 1996 10:43:45 GMT References: <1996Sep06.221345.8286@unam.mx> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Sep06.221345.8286@unam.mx>, skim@unam.mx (Seo-yeon Kim) 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. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Jens Hernández | jhernandez@panix.com PGP Key fingerprint: 2AFA AE59 DE79 BC0F "Keep the channels open." From blindqvist@titech.ac.jp Mon Sep 09 15:56:45 1996 Path: ashpoly!cascade!transat!ukc!fennimore!titech!blindqvist From: blindqvist@titech.ac.jp (Bill Lindqvist) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep09.155645.3858@titech.ac.jp> Date: Mon, 09 Sep 1996 15:56:45 GMT References: <1996Sep06.221345.8286@unam.mx> <1996Sep08.104345.6645@panix.com> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Sep08.104345.6645@panix.com>, jhernandez@panix.com (Jens Hernández) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. > Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Bill Lindqvist "Do not worship the copy." Amiga 3000T / AmigaOS 3.1