From pokonkwo@netcom.com Tue Apr 18 17:20:22 1995 Path: ashpoly!cascade!brgate!saturno!netcom!pokonkwo From: pokonkwo@netcom.com (Pavel Okonkwo) Newsgroups: comp.sys.m68k Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr18.172022.1153@netcom.com> Date: Tue, 18 Apr 1995 17:20:22 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.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! -- Pavel Okonkwo Opinions expressed are solely my own and not those of NETCOM On-Line Communication Services. ------------------------------------------------------------ From eweber@berkeley.edu Wed Apr 19 14:50:22 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!berkeley!eweber From: eweber@berkeley.edu (Emi Weber) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr19.145022.6147@berkeley.edu> Date: Wed, 19 Apr 1995 14:50:22 GMT References: <1995Apr18.172022.1153@netcom.com> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Apr18.172022.1153@netcom.com>, pokonkwo@netcom.com (Pavel Okonkwo) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Emi Weber Tape trading list upon request. SASE required for international mail. From rdubois@titech.ac.jp Wed Apr 19 17:12:22 1995 Path: ashpoly!cascade!transat!ukc!fennimore!titech!rdubois From: rdubois@titech.ac.jp (Rodrigo Dubois) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr19.171222.9909@titech.ac.jp> Date: Wed, 19 Apr 1995 17:12:22 GMT References: <1995Apr18.172022.1153@netcom.com> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Apr18.172022.1153@netcom.com>, pokonkwo@netcom.com (Pavel Okonkwo) 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. -- Rodrigo Dubois US Robotics Courier V.34 @ 14,400 bps "In theory there is no difference between theory and practice." From echoi@tum.de Thu Apr 20 03:34:22 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!tum!echoi From: echoi@tum.de (Emi Choi) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr20.033422.6954@tum.de> Date: Thu, 20 Apr 1995 03:34:22 GMT References: <1995Apr18.172022.1153@netcom.com> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Apr18.172022.1153@netcom.com>, pokonkwo@netcom.com (Pavel Okonkwo) 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. -- Emi Choi Opinions expressed are solely my own and not those of Technische Universität München. ------------------------------------------------------------ From tsokolov@kiae.su Thu Apr 20 10:36:22 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!kiae!tsokolov From: tsokolov@kiae.su (Tomas Sokolov) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr20.103622.6596@kiae.su> Date: Thu, 20 Apr 1995 10:36:22 GMT References: <1995Apr18.172022.1153@netcom.com> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Apr18.172022.1153@netcom.com>, pokonkwo@netcom.com (Pavel Okonkwo) 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! -- Tomas Sokolov -- Kurchatov Institute of Atomic Energy, Moscow "5 sigma is a discovery. 7 is a question."