From jkuznetsov@netcom.com Sat Apr 27 19:25:54 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!netcom!jkuznetsov From: jkuznetsov@netcom.com (Julien Kuznetsov) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr27.192554.7366@netcom.com> Date: Sat, 27 Apr 1996 19:25:54 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Julien Kuznetsov *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0 From msmirnov@mit.edu Mon Apr 29 06:33:54 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!mit!msmirnov From: msmirnov@mit.edu (Mateo Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Apr29.063354.3468@mit.edu> Date: Mon, 29 Apr 1996 06:33:54 GMT References: <1996Apr27.192554.7366@netcom.com> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Apr27.192554.7366@netcom.com>, jkuznetsov@netcom.com (Julien Kuznetsov) 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. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Mateo Smirnov | msmirnov@mit.edu PGP Key fingerprint: E8CD FC1D B3F0 A25B "Keep the channels open." From bito@mindspring.com Wed May 01 05:42:54 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!mindspring!bito From: bito@mindspring.com (Bastien Ito) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May01.054254.2623@mindspring.com> Date: Wed, 01 May 1996 05:42:54 GMT References: <1996Apr27.192554.7366@netcom.com> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Apr27.192554.7366@netcom.com>, jkuznetsov@netcom.com (Julien Kuznetsov) 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. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Bastien Ito | bito@mindspring.com PGP Key fingerprint: 105D 6E5B 6C3E 3784 "Keep the channels open." From lgonzalez@illinois.edu Thu May 02 20:14:54 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!illinois!lgonzalez From: lgonzalez@illinois.edu (Lucia González) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May02.201454.7705@illinois.edu> Date: Thu, 02 May 1996 20:14:54 GMT References: <1996Apr27.192554.7366@netcom.com> <1996May01.054254.2623@mindspring.com> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 8 In article <1996May01.054254.2623@mindspring.com>, bito@mindspring.com (Bastien Ito) writes: > PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Lucia González -- University of Illinois Urbana-Champaign "We don't sign stars. We build them." From keriksson@utexas.edu Fri May 03 14:28:54 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!utexas!keriksson From: keriksson@utexas.edu (Karen Eriksson) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May03.142854.6367@utexas.edu> Date: Fri, 03 May 1996 14:28:54 GMT References: <1996Apr27.192554.7366@netcom.com> <1996May01.054254.2623@mindspring.com> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996May01.054254.2623@mindspring.com>, bito@mindspring.com (Bastien Ito) writes: > PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. PGP Public key available via finger or upon request. -- Karen Eriksson SupraFAXModem 28.8 @ 33,600 bps "The carrier frequency does not drift by accident."