From rweber@kth.se Sat Jul 27 05:18:34 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!kth!rweber From: rweber@kth.se (Rodrigo Weber) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul27.051834.1520@kth.se> Date: Sat, 27 Jul 1996 05:18:34 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: NewsWatcher 2.0b24 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. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Rodrigo Weber US Robotics Courier V.34 @ 33,600 bps "Extraordinary claims require extraordinary spectra." From kvasiliev@clari.net Sun Jul 28 14:00:34 1996 Path: ashpoly!cascade!mxgate!coyoacan!clari!kvasiliev From: kvasiliev@clari.net (Kenji Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Jul28.140034.9914@clari.net> Date: Sun, 28 Jul 1996 14:00:34 GMT References: <1996Jul27.051834.1520@kth.se> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Jul27.051834.1520@kth.se>, rweber@kth.se (Rodrigo Weber) 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? -- Kenji Vasiliev -- ClariNet Communications Corp "A soul is not exclusive to biology."