From hmoreau@demon.co.uk Sun Dec 08 19:17:26 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!demon!hmoreau From: hmoreau@demon.co.uk (Heather Moreau) Newsgroups: comp.sys.m68k Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec08.191726.6153@demon.co.uk> Date: Sun, 08 Dec 1996 19:17:26 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: Netscape 1.1N Lines: 11 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Heather Moreau "Marcus is not one man." PC-9821Ap2 (NEC) / FreeBSD 2.1 From kgirard@uu.net Sun Dec 08 20:06:26 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!uu!kgirard From: kgirard@uu.net (Kenji Girard) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec08.200626.1053@uu.net> Date: Sun, 08 Dec 1996 20:06:26 GMT References: <1996Dec08.191726.6153@demon.co.uk> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Dec08.191726.6153@demon.co.uk>, hmoreau@demon.co.uk (Heather Moreau) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- === Kenji Girard === Dept of Electrical Engineering, UUNET Technologies, Falls Church VA "The hatch is open. Is anyone listening?" From rtakahashi@pipeline.com Sun Dec 08 22:48:26 1996 Path: ashpoly!cascade!mxgate!coyoacan!pipeline!rtakahashi From: rtakahashi@pipeline.com (Rodrigo Takahashi) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec08.224826.7117@pipeline.com> Date: Sun, 08 Dec 1996 22:48:26 GMT References: <1996Dec08.191726.6153@demon.co.uk> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 12 In article <1996Dec08.191726.6153@demon.co.uk>, hmoreau@demon.co.uk (Heather Moreau) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Rodrigo Takahashi Zyxel U-1496E @ 33,600 bps "Measuring a record you own is listening, not piracy." From asato@uni-hamburg.de Mon Dec 09 11:52:26 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!uni-hamburg!asato From: asato@uni-hamburg.de (Astrid Sato) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec09.115226.7630@uni-hamburg.de> Date: Mon, 09 Dec 1996 11:52:26 GMT References: <1996Dec08.191726.6153@demon.co.uk> <1996Dec08.200626.1053@uu.net> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Dec08.200626.1053@uu.net>, kgirard@uu.net (Kenji Girard) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Astrid Sato "Tape doesn't lie at 02:14. Ears do." Atari Falcon 030 / NEXTSTEP 3.3