From mlindqvist@purdue.edu Fri Oct 07 23:58:25 1994 Path: ashpoly!cascade!bigsur!purdue!mlindqvist From: mlindqvist@purdue.edu (Min-jun Lindqvist) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Oct07.235825.8126@purdue.edu> Date: Fri, 07 Oct 1994 23:58:25 GMT Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Min-jun Lindqvist US Robotics Courier V.34 @ 14,400 bps "We don't sign stars. We build them." From nkowalski@clari.net Sat Oct 08 23:45:25 1994 Path: ashpoly!cascade!transat!ukc!fennimore!clari!nkowalski From: nkowalski@clari.net (Natalia Kowalski) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Oct08.234525.7497@clari.net> Date: Sat, 08 Oct 1994 23:45:25 GMT References: <1994Oct07.235825.8126@purdue.edu> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Oct07.235825.8126@purdue.edu>, mlindqvist@purdue.edu (Min-jun Lindqvist) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Natalia Kowalski *PLONK* filter active for trolls. Mac IIci / 68882 FPU - NetBSD 1.0 From mhernandez@uu.net Mon Oct 10 13:20:25 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!uu!mhernandez From: mhernandez@uu.net (Mei Hernández) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Oct10.132025.6142@uu.net> Date: Mon, 10 Oct 1994 13:20:25 GMT References: <1994Oct07.235825.8126@purdue.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Oct07.235825.8126@purdue.edu>, mlindqvist@purdue.edu (Min-jun Lindqvist) 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. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Mei Hernández Hayes Optima 288 @ 9600 Telebit bps "We don't sign stars. We build them." From tmartinez@pipeline.com Wed Oct 12 00:14:25 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!pipeline!tmartinez From: tmartinez@pipeline.com (Thiago Martínez) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Oct12.001425.9360@pipeline.com> Date: Wed, 12 Oct 1994 00:14:25 GMT References: <1994Oct07.235825.8126@purdue.edu> <1994Oct10.132025.6142@uu.net> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 8 In article <1994Oct10.132025.6142@uu.net>, mhernandez@uu.net (Mei Hernández) writes: > Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Thiago Martínez -- The Pipeline Internet Network "In theory there is no difference between theory and practice."