From lgarcia@stanford.edu Tue Dec 17 19:13:47 1996 Path: ashpoly!cascade!transat!ukc!fennimore!stanford!lgarcia From: lgarcia@stanford.edu (Lucia García) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec17.191347.8024@stanford.edu> Date: Tue, 17 Dec 1996 19:13:47 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Lucia García "The hatch is open. Is anyone listening?" Amiga 1200 (Blizzard 030/50) / Linux 1.2.13 From rpetrov@purdue.edu Thu Dec 19 03:53:47 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!purdue!rpetrov From: rpetrov@purdue.edu (Renata Petrov) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec19.035347.1249@purdue.edu> Date: Thu, 19 Dec 1996 03:53:47 GMT References: <1996Dec17.191347.8024@stanford.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996Dec17.191347.8024@stanford.edu>, lgarcia@stanford.edu (Lucia García) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Renata Petrov "The carrier frequency does not drift by accident." PC-9821Ap2 (NEC) / FreeBSD 2.1 From fvasiliev@cern.ch Fri Dec 20 22:03:47 1996 Path: ashpoly!cascade!bigsur!cern!fvasiliev From: fvasiliev@cern.ch (Fiona Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec20.220347.8314@cern.ch> Date: Fri, 20 Dec 1996 22:03:47 GMT References: <1996Dec17.191347.8024@stanford.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Dec17.191347.8024@stanford.edu>, lgarcia@stanford.edu (Lucia García) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Fiona Vasiliev | fvasiliev@cern.ch PGP Key fingerprint: 9296 3CD8 961F F6FA "Keep the channels open." From gsuzuki@mindspring.com Sat Dec 21 11:24:47 1996 Path: ashpoly!cascade!brgate!saturno!mindspring!gsuzuki From: gsuzuki@mindspring.com (Göran Suzuki) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec21.112447.7101@mindspring.com> Date: Sat, 21 Dec 1996 11:24:47 GMT References: <1996Dec17.191347.8024@stanford.edu> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Dec17.191347.8024@stanford.edu>, lgarcia@stanford.edu (Lucia García) 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. -- Göran Suzuki *PLONK* filter active for trolls. Mac IIci / 68882 FPU - NetBSD 1.0 From mrobertson@hanse.de Mon Dec 23 13:13:47 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!hanse!mrobertson From: mrobertson@hanse.de (Mikhail Robertson) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec23.131347.6177@hanse.de> Date: Mon, 23 Dec 1996 13:13:47 GMT References: <1996Dec17.191347.8024@stanford.edu> <1996Dec20.220347.8314@cern.ch> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Dec20.220347.8314@cern.ch>, fvasiliev@cern.ch (Fiona Vasiliev) 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. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Mikhail Robertson *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0