From ecampbell@mindspring.com Sat May 25 10:10:57 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!mindspring!ecampbell From: ecampbell@mindspring.com (Elaine Campbell) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May25.101057.2407@mindspring.com> Date: Sat, 25 May 1996 10:10:57 GMT Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: TIN [version 1.2 PL2] 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Elaine Campbell Opinions expressed are solely my own and not those of MindSpring Enterprises. ------------------------------------------------------------ From mfournier@titech.ac.jp Sat May 25 14:25:57 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!titech!mfournier From: mfournier@titech.ac.jp (Mike Fournier) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May25.142557.7827@titech.ac.jp> Date: Sat, 25 May 1996 14:25:57 GMT References: <1996May25.101057.2407@mindspring.com> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996May25.101057.2407@mindspring.com>, ecampbell@mindspring.com (Elaine Campbell) 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. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Mike Fournier Tape trading list upon request. SASE required for international mail. From mpark@illinois.edu Sun May 26 15:26:57 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!illinois!mpark From: mpark@illinois.edu (Marisol Park) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May26.152657.3433@illinois.edu> Date: Sun, 26 May 1996 15:26:57 GMT References: <1996May25.101057.2407@mindspring.com> <1996May25.142557.7827@titech.ac.jp> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996May25.142557.7827@titech.ac.jp>, mfournier@titech.ac.jp (Mike Fournier) 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 Park "In theory there is no difference between theory and practice." 486DX2/66 (Linux 1.2.13) / FreeBSD 2.1 From tgirard@stanford.edu Mon May 27 18:13:57 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!stanford!tgirard From: tgirard@stanford.edu (Tyler Girard) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996May27.181357.3950@stanford.edu> Date: Mon, 27 May 1996 18:13:57 GMT References: <1996May25.101057.2407@mindspring.com> <1996May25.142557.7827@titech.ac.jp> <1996May26.152657.3433@illinois.edu> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996May26.152657.3433@illinois.edu>, mpark@illinois.edu (Marisol Park) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Tyler Girard "Measuring a record you own is listening, not piracy." Amiga 3000T / NEXTSTEP 3.3