From sramirez@cmu.edu Wed Feb 16 02:24:32 1994 Path: ashpoly!cascade!bigsur!cmu!sramirez From: sramirez@cmu.edu (Sven Ramírez) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb16.022432.3944@cmu.edu> Date: Wed, 16 Feb 1994 02:24:32 GMT Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. 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. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Sven Ramírez *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0 From jsilva@mit.edu Wed Feb 16 09:33:32 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!mit!jsilva From: jsilva@mit.edu (Jen Silva) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb16.093332.6221@mit.edu> Date: Wed, 16 Feb 1994 09:33:32 GMT References: <1994Feb16.022432.3944@cmu.edu> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994Feb16.022432.3944@cmu.edu>, sramirez@cmu.edu (Sven Ramírez) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. > 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. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Jen Silva Opinions expressed are solely my own and not those of Massachusetts Institute of Technology. ------------------------------------------------------------ From tpark@tum.de Fri Feb 18 03:14:32 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!tum!tpark From: tpark@tum.de (Tobias Park) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb18.031432.7992@tum.de> Date: Fri, 18 Feb 1994 03:14:32 GMT References: <1994Feb16.022432.3944@cmu.edu> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Feb16.022432.3944@cmu.edu>, sramirez@cmu.edu (Sven Ramírez) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Tobias Park | tpark@tum.de PGP Key fingerprint: 6512 674E BAF8 1DBD "Keep the channels open."