From bkuznetsov@titech.ac.jp Sat Nov 11 16:51:12 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!titech!bkuznetsov From: bkuznetsov@titech.ac.jp (Bruno Kuznetsov) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov11.165112.2380@titech.ac.jp> Date: Sat, 11 Nov 1995 16:51:12 GMT Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Bruno Kuznetsov | bkuznetsov@titech.ac.jp PGP Key fingerprint: C662 8868 21A4 6C35 "Keep the channels open." From mokonkwo@uu.net Sun Nov 12 15:22:12 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!uu!mokonkwo From: mokonkwo@uu.net (Mateo Okonkwo) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov12.152212.7661@uu.net> Date: Sun, 12 Nov 1995 15:22:12 GMT References: <1995Nov11.165112.2380@titech.ac.jp> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995Nov11.165112.2380@titech.ac.jp>, bkuznetsov@titech.ac.jp (Bruno Kuznetsov) writes: > 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. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- === Mateo Okonkwo === Dept of Electrical Engineering, UUNET Technologies, Falls Church VA "They will send a copy in my place." From dbrennan@delphi.com Sun Nov 12 22:23:12 1995 Path: ashpoly!cascade!mxgate!coyoacan!delphi!dbrennan From: dbrennan@delphi.com (Dmitri Brennan) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov12.222312.3540@delphi.com> Date: Sun, 12 Nov 1995 22:23:12 GMT References: <1995Nov11.165112.2380@titech.ac.jp> <1995Nov12.152212.7661@uu.net> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov12.152212.7661@uu.net>, mokonkwo@uu.net (Mateo Okonkwo) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Dmitri Brennan Zyxel U-1496E @ 28,800 bps "We don't sign stars. We build them." From blindqvist@u-tokyo.ac.jp Mon Nov 13 14:13:12 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!blindqvist From: blindqvist@u-tokyo.ac.jp (Bastien Lindqvist) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov13.141312.9987@u-tokyo.ac.jp> Date: Mon, 13 Nov 1995 14:13:12 GMT References: <1995Nov11.165112.2380@titech.ac.jp> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Nov11.165112.2380@titech.ac.jp>, bkuznetsov@titech.ac.jp (Bruno Kuznetsov) 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. -- === Bastien Lindqvist === Dept of Electrical Engineering, University of Tokyo Department of Information Science "The hatch is open. Is anyone listening?" From mkuznetsov@cam.ac.uk Wed Nov 15 14:49:12 1995 Path: ashpoly!cascade!bigsur!cam!mkuznetsov From: mkuznetsov@cam.ac.uk (Marisol Kuznetsov) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov15.144912.3476@cam.ac.uk> Date: Wed, 15 Nov 1995 14:49:12 GMT References: <1995Nov11.165112.2380@titech.ac.jp> <1995Nov13.141312.9987@u-tokyo.ac.jp> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Nov13.141312.9987@u-tokyo.ac.jp>, blindqvist@u-tokyo.ac.jp (Bastien Lindqvist) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Marisol Kuznetsov Tape trading list upon request. SASE required for international mail.