From amartinez@pipeline.com Thu Jul 27 03:04:02 1995 Path: ashpoly!cascade!transat!ukc!fennimore!pipeline!amartinez From: amartinez@pipeline.com (Astrid Martínez) Newsgroups: comp.sys.m68k Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jul27.030402.2620@pipeline.com> Date: Thu, 27 Jul 1995 03:04:02 GMT Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. 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! -- Astrid Martínez "Measuring a record you own is listening, not piracy." NeXTstation Turbo Color / AmigaOS 3.1 From gperez@demon.co.uk Fri Jul 28 23:40:02 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!demon!gperez From: gperez@demon.co.uk (Göran Pérez) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jul28.234002.5036@demon.co.uk> Date: Fri, 28 Jul 1995 23:40:02 GMT References: <1995Jul27.030402.2620@pipeline.com> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Jul27.030402.2620@pipeline.com>, amartinez@pipeline.com (Astrid Martínez) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Göran Pérez Tape trading list upon request. SASE required for international mail. From ftanaka@uu.net Sun Jul 30 23:25:02 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!uu!ftanaka From: ftanaka@uu.net (Fiona Tanaka) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jul30.232502.4160@uu.net> Date: Sun, 30 Jul 1995 23:25:02 GMT References: <1995Jul27.030402.2620@pipeline.com> <1995Jul28.234002.5036@demon.co.uk> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jul28.234002.5036@demon.co.uk>, gperez@demon.co.uk (Göran Pérez) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Fiona Tanaka *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0