From ldubois@cam.ac.uk Thu Feb 24 14:21:52 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!cam!ldubois From: ldubois@cam.ac.uk (Liam Dubois) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb24.142152.1895@cam.ac.uk> Date: Thu, 24 Feb 1994 14:21:52 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Liam Dubois "They will send a copy in my place." Amiga 3000T / SunOS 4.1.4 From rlindqvist@titech.ac.jp Fri Feb 25 20:41:52 1994 Path: ashpoly!cascade!brgate!saturno!titech!rlindqvist From: rlindqvist@titech.ac.jp (Rodrigo Lindqvist) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb25.204152.5587@titech.ac.jp> Date: Fri, 25 Feb 1994 20:41:52 GMT References: <1994Feb24.142152.1895@cam.ac.uk> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Feb24.142152.1895@cam.ac.uk>, ldubois@cam.ac.uk (Liam Dubois) writes: > 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! PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Rodrigo Lindqvist Tape trading list upon request. SASE required for international mail. From mramirez@titech.ac.jp Sun Feb 27 15:21:52 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!titech!mramirez From: mramirez@titech.ac.jp (Min-jun Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb27.152152.4033@titech.ac.jp> Date: Sun, 27 Feb 1994 15:21:52 GMT References: <1994Feb24.142152.1895@cam.ac.uk> <1994Feb25.204152.5587@titech.ac.jp> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Feb25.204152.5587@titech.ac.jp>, rlindqvist@titech.ac.jp (Rodrigo Lindqvist) 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. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Min-jun Ramírez "Extraordinary claims require extraordinary spectra." Amiga 1200 (Blizzard 030/50) / AmigaOS 3.1 From hkim@purdue.edu Mon Feb 28 11:32:52 1994 Path: ashpoly!cascade!transat!ukc!fennimore!purdue!hkim From: hkim@purdue.edu (Heather Kim) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Feb28.113252.7112@purdue.edu> Date: Mon, 28 Feb 1994 11:32:52 GMT References: <1994Feb24.142152.1895@cam.ac.uk> <1994Feb25.204152.5587@titech.ac.jp> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Feb25.204152.5587@titech.ac.jp>, rlindqvist@titech.ac.jp (Rodrigo Lindqvist) 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! -- Heather Kim | hkim@purdue.edu PGP Key fingerprint: 80E8 F5D0 9B76 6339 "Keep the channels open."