From hnilsson@kiae.su Fri Jun 23 06:50:41 1995 Path: ashpoly!cascade!transat!ukc!fennimore!kiae!hnilsson From: hnilsson@kiae.su (Hugo Nilsson) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun23.065041.3245@kiae.su> Date: Fri, 23 Jun 1995 06:50:41 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! 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? -- Hugo Nilsson Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow. ------------------------------------------------------------ From bmartinez@panix.com Fri Jun 23 16:18:41 1995 Path: ashpoly!cascade!transat!ukc!fennimore!panix!bmartinez From: bmartinez@panix.com (Bruno Martínez) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun23.161841.4105@panix.com> Date: Fri, 23 Jun 1995 16:18:41 GMT References: <1995Jun23.065041.3245@kiae.su> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Jun23.065041.3245@kiae.su>, hnilsson@kiae.su (Hugo Nilsson) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Bruno Martínez *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0