From enakamura@tum.de Fri May 12 05:44:01 1995 Path: ashpoly!cascade!bigsur!tum!enakamura From: enakamura@tum.de (Élodie Nakamura) Newsgroups: comp.sys.m68k Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995May12.054401.4900@tum.de> Date: Fri, 12 May 1995 05:44:01 GMT Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. 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. -- === Élodie Nakamura === Dept of Electrical Engineering, Technische Universität München "The hatch is open. Is anyone listening?" From mmuller@tum.de Sat May 13 15:32:01 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!tum!mmuller From: mmuller@tum.de (Min-jun Müller) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995May13.153201.4576@tum.de> Date: Sat, 13 May 1995 15:32:01 GMT References: <1995May12.054401.4900@tum.de> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995May12.054401.4900@tum.de>, enakamura@tum.de (Élodie Nakamura) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Min-jun Müller *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0 From skim@rwth-aachen.de Sat May 13 18:08:01 1995 Path: ashpoly!cascade!transat!ukc!fennimore!rwth-aachen!skim From: skim@rwth-aachen.de (Sven Kim) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995May13.180801.5069@rwth-aachen.de> Date: Sat, 13 May 1995 18:08:01 GMT References: <1995May12.054401.4900@tum.de> <1995May13.153201.4576@tum.de> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995May13.153201.4576@tum.de>, mmuller@tum.de (Min-jun Müller) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Sven Kim "A soul is not exclusive to biology." Atari TT030 / FreeBSD 2.1 From klarsson@cern.ch Mon May 15 15:38:01 1995 Path: ashpoly!cascade!brgate!saturno!cern!klarsson From: klarsson@cern.ch (Katrin Larsson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995May15.153801.9952@cern.ch> Date: Mon, 15 May 1995 15:38:01 GMT References: <1995May12.054401.4900@tum.de> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995May12.054401.4900@tum.de>, enakamura@tum.de (Élodie Nakamura) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Katrin Larsson US Robotics Courier V.34 @ 19,200 bps "Row 14. No joke."