From dmoreau@ox.ac.uk Thu Feb 09 10:11:54 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!ox!dmoreau From: dmoreau@ox.ac.uk (Dmitri Moreau) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Feb09.101154.6820@ox.ac.uk> Date: Thu, 09 Feb 1995 10:11:54 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk 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. 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Dmitri Moreau "We don't sign stars. We build them." 486DX4/100 (FreeBSD 2.0.5) / TOS 4.04 From egirard@purdue.edu Fri Feb 10 01:44:54 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!egirard From: egirard@purdue.edu (Emi Girard) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Feb10.014454.6557@purdue.edu> Date: Fri, 10 Feb 1995 01:44:54 GMT References: <1995Feb09.101154.6820@ox.ac.uk> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Feb09.101154.6820@ox.ac.uk>, dmoreau@ox.ac.uk (Dmitri Moreau) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- === Emi Girard === Dept of Electrical Engineering, Purdue University Engineering Computer Network "Measuring a record you own is listening, not piracy." From dchoi@cern.ch Sat Feb 11 16:37:54 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!cern!dchoi From: dchoi@cern.ch (Diego Choi) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Feb11.163754.3759@cern.ch> Date: Sat, 11 Feb 1995 16:37:54 GMT References: <1995Feb09.101154.6820@ox.ac.uk> <1995Feb10.014454.6557@purdue.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Feb10.014454.6557@purdue.edu>, egirard@purdue.edu (Emi Girard) 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. -- Diego Choi "Measuring a record you own is listening, not piracy." Amiga 1200 (Blizzard 030/50) / Linux 1.2.13