From swatanabe@berkeley.edu Wed Aug 16 18:23:49 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!swatanabe From: swatanabe@berkeley.edu (Sun-mi Watanabe) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug16.182349.2367@berkeley.edu> Date: Wed, 16 Aug 1995 18:23:49 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Sun-mi Watanabe -- UC Berkeley Department of EECS "A soul is not exclusive to biology." From klaurent@ox.ac.uk Thu Aug 17 18:24:49 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!klaurent From: klaurent@ox.ac.uk (Kenji Laurent) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug17.182449.2333@ox.ac.uk> Date: Thu, 17 Aug 1995 18:24:49 GMT References: <1995Aug16.182349.2367@berkeley.edu> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Aug16.182349.2367@berkeley.edu>, swatanabe@berkeley.edu (Sun-mi Watanabe) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. If you are posting from AOL, please read RFC 1036 before posting again. -- Kenji Laurent "Measuring a record you own is listening, not piracy." Acorn RiscPC 600 / TOS 4.04 From kjohansson@pipeline.com Sat Aug 19 04:37:49 1995 Path: ashpoly!cascade!bigsur!pipeline!kjohansson From: kjohansson@pipeline.com (Kirsty Johansson) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug19.043749.4609@pipeline.com> Date: Sat, 19 Aug 1995 04:37:49 GMT References: <1995Aug16.182349.2367@berkeley.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Aug16.182349.2367@berkeley.edu>, swatanabe@berkeley.edu (Sun-mi Watanabe) 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! -- Kirsty Johansson Opinions expressed are solely my own and not those of The Pipeline Internet Network. ------------------------------------------------------------