From rlaurent@panix.com Wed Jul 27 02:02:26 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!panix!rlaurent From: rlaurent@panix.com (Rodrigo Laurent) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul27.020226.1186@panix.com> Date: Wed, 27 Jul 1994 02:02:26 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 10 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. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Rodrigo Laurent -- Public Access Unix of New York "Tape doesn't lie at 02:14. Ears do." From ssmirnov@berkeley.edu Thu Jul 28 01:23:26 1994 Path: ashpoly!cascade!brgate!saturno!berkeley!ssmirnov From: ssmirnov@berkeley.edu (Steve Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul28.012326.2931@berkeley.edu> Date: Thu, 28 Jul 1994 01:23:26 GMT References: <1994Jul27.020226.1186@panix.com> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1994Jul27.020226.1186@panix.com>, rlaurent@panix.com (Rodrigo Laurent) 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? -- Steve Smirnov -- UC Berkeley Department of EECS "The carrier frequency does not drift by accident." From fivanov@cmu.edu Sat Jul 30 05:11:26 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cmu!fivanov From: fivanov@cmu.edu (Freya Ivanov) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul30.051126.4952@cmu.edu> Date: Sat, 30 Jul 1994 05:11:26 GMT References: <1994Jul27.020226.1186@panix.com> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1994Jul27.020226.1186@panix.com>, rlaurent@panix.com (Rodrigo Laurent) writes: > 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. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Freya Ivanov *PLONK* filter active for trolls. Sun SparcStation 20 - NetBSD 1.0 From awatanabe@berkeley.edu Sat Jul 30 19:30:26 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!berkeley!awatanabe From: awatanabe@berkeley.edu (Astrid Watanabe) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul30.193026.9737@berkeley.edu> Date: Sat, 30 Jul 1994 19:30:26 GMT References: <1994Jul27.020226.1186@panix.com> <1994Jul30.051126.4952@cmu.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Jul30.051126.4952@cmu.edu>, fivanov@cmu.edu (Freya Ivanov) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Astrid Watanabe Opinions expressed are solely my own and not those of UC Berkeley Department of EECS. ------------------------------------------------------------