From jmoreno@unam.mx Tue Apr 05 16:12:19 1994 Path: ashpoly!cascade!bigsur!unam!jmoreno From: jmoreno@unam.mx (Jen Moreno) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr05.161219.8073@unam.mx> Date: Tue, 05 Apr 1994 16:12:19 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: Netscape 1.1N Lines: 11 Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. 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! -- Jen Moreno | jmoreno@unam.mx PGP Key fingerprint: 538A 2F77 FFE9 45C0 "Keep the channels open." From tcampbell@earthlink.net Wed Apr 06 22:28:19 1994 Path: ashpoly!cascade!mxgate!coyoacan!earthlink!tcampbell From: tcampbell@earthlink.net (Tobias Campbell) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr06.222819.8268@earthlink.net> Date: Wed, 06 Apr 1994 22:28:19 GMT References: <1994Apr05.161219.8073@unam.mx> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1994Apr05.161219.8073@unam.mx>, jmoreno@unam.mx (Jen Moreno) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. > 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. Top-posters will be placed in my ~/.killfile without notice. -- Tobias Campbell | tcampbell@earthlink.net PGP Key fingerprint: BDA9 AA54 F399 3FBE "Keep the channels open." From nsokolov@netcom.com Thu Apr 07 19:52:19 1994 Path: ashpoly!cascade!mxgate!coyoacan!netcom!nsokolov From: nsokolov@netcom.com (Nadia Sokolov) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr07.195219.3776@netcom.com> Date: Thu, 07 Apr 1994 19:52:19 GMT References: <1994Apr05.161219.8073@unam.mx> <1994Apr06.222819.8268@earthlink.net> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Apr06.222819.8268@earthlink.net>, tcampbell@earthlink.net (Tobias Campbell) 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. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Nadia Sokolov "We don't sign stars. We build them." PC-9821Ap2 (NEC) / NEXTSTEP 3.3