From jmuller@hanse.de Sun Apr 09 14:32:27 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!hanse!jmuller From: jmuller@hanse.de (Joachim Müller) Newsgroups: comp.sys.m68k Subject: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr09.143227.6367@hanse.de> Date: Sun, 09 Apr 1995 14:32:27 GMT Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de 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. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. 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! -- Joachim Müller | jmuller@hanse.de PGP Key fingerprint: 3A73 DC04 738B 5915 "Keep the channels open." From plopez@stanford.edu Mon Apr 10 16:42:27 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!stanford!plopez From: plopez@stanford.edu (Pavel López) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr10.164227.4306@stanford.edu> Date: Mon, 10 Apr 1995 16:42:27 GMT References: <1995Apr09.143227.6367@hanse.de> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Apr09.143227.6367@hanse.de>, jmuller@hanse.de (Joachim Müller) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Pavel López Practical Peripherals 14.4 @ 14,400 bps "We don't sign stars. We build them." From roliveira@unam.mx Wed Apr 12 05:52:27 1995 Path: ashpoly!cascade!brgate!saturno!unam!roliveira From: roliveira@unam.mx (Renata Oliveira) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr12.055227.7389@unam.mx> Date: Wed, 12 Apr 1995 05:52:27 GMT References: <1995Apr09.143227.6367@hanse.de> <1995Apr10.164227.4306@stanford.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Apr10.164227.4306@stanford.edu>, plopez@stanford.edu (Pavel López) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Renata Oliveira Tape trading list upon request. SASE required for international mail. From rchoi@purdue.edu Wed Apr 12 08:05:27 1995 Path: ashpoly!cascade!transat!ukc!fennimore!purdue!rchoi From: rchoi@purdue.edu (Renata Choi) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr12.080527.1351@purdue.edu> Date: Wed, 12 Apr 1995 08:05:27 GMT References: <1995Apr09.143227.6367@hanse.de> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Apr09.143227.6367@hanse.de>, jmuller@hanse.de (Joachim Müller) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Renata Choi Practical Peripherals 14.4 @ 33,600 bps "Marcus is not one man." From acampbell@uu.net Wed Apr 12 10:28:27 1995 Path: ashpoly!cascade!mxgate!coyoacan!uu!acampbell From: acampbell@uu.net (Astrid Campbell) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr12.102827.7996@uu.net> Date: Wed, 12 Apr 1995 10:28:27 GMT References: <1995Apr09.143227.6367@hanse.de> <1995Apr10.164227.4306@stanford.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Apr10.164227.4306@stanford.edu>, plopez@stanford.edu (Pavel López) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Astrid Campbell Practical Peripherals 14.4 @ 19,200 bps "There are 14 nodes and only 10 countries. Count again."