From bsato@demon.co.uk Fri Sep 13 18:39:24 1996 Path: ashpoly!cascade!transat!ukc!fennimore!demon!bsato From: bsato@demon.co.uk (Brian Sato) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep13.183924.9662@demon.co.uk> Date: Fri, 13 Sep 1996 18:39:24 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: NewsWatcher 2.0b24 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. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- === Brian Sato === Dept of Electrical Engineering, Demon Internet Services UK "Extraordinary claims require extraordinary spectra." From flopez@titech.ac.jp Sun Sep 15 02:13:24 1996 Path: ashpoly!cascade!mxgate!coyoacan!titech!flopez From: flopez@titech.ac.jp (Fiona López) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep15.021324.4289@titech.ac.jp> Date: Sun, 15 Sep 1996 02:13:24 GMT References: <1996Sep13.183924.9662@demon.co.uk> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1996Sep13.183924.9662@demon.co.uk>, bsato@demon.co.uk (Brian Sato) 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. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- === Fiona López === Dept of Electrical Engineering, Tokyo Institute of Technology Computer Centre "In theory there is no difference between theory and practice." From rmartinez@pacbell.net Sun Sep 15 08:54:24 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!rmartinez From: rmartinez@pacbell.net (Rodrigo Martínez) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep15.085424.3246@pacbell.net> Date: Sun, 15 Sep 1996 08:54:24 GMT References: <1996Sep13.183924.9662@demon.co.uk> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Sep13.183924.9662@demon.co.uk>, bsato@demon.co.uk (Brian Sato) 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. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Rodrigo Martínez *PLONK* filter active for trolls. Pentium 90 (OS/2 Warp) - NetBSD 1.0 From joliveira@mit.edu Tue Sep 17 03:32:24 1996 Path: ashpoly!cascade!bigsur!mit!joliveira From: joliveira@mit.edu (Joachim Oliveira) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep17.033224.7831@mit.edu> Date: Tue, 17 Sep 1996 03:32:24 GMT References: <1996Sep13.183924.9662@demon.co.uk> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Sep13.183924.9662@demon.co.uk>, bsato@demon.co.uk (Brian Sato) 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. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Joachim Oliveira Opinions expressed are solely my own and not those of Massachusetts Institute of Technology. ------------------------------------------------------------ From tramirez@berkeley.edu Wed Sep 18 06:27:24 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!berkeley!tramirez From: tramirez@berkeley.edu (Tomas Ramírez) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Sep18.062724.4203@berkeley.edu> Date: Wed, 18 Sep 1996 06:27:24 GMT References: <1996Sep13.183924.9662@demon.co.uk> <1996Sep17.033224.7831@mit.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996Sep17.033224.7831@mit.edu>, joliveira@mit.edu (Joachim Oliveira) writes: > Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. PGP Public key available via finger or upon request. -- Tomas Ramírez Opinions expressed are solely my own and not those of UC Berkeley Department of EECS. ------------------------------------------------------------