From aschneider@utexas.edu Thu Feb 01 08:58:41 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!utexas!aschneider From: aschneider@utexas.edu (Astrid Schneider) Newsgroups: comp.sys.m68k Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Feb01.085841.3188@utexas.edu> Date: Thu, 01 Feb 1996 08:58:41 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 Lines: 10 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. -- Astrid Schneider Tape trading list upon request. SASE required for international mail. From msmirnov@netcom.com Thu Feb 01 14:33:41 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!netcom!msmirnov From: msmirnov@netcom.com (Marisol Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Feb01.143341.9922@netcom.com> Date: Thu, 01 Feb 1996 14:33:41 GMT References: <1996Feb01.085841.3188@utexas.edu> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Feb01.085841.3188@utexas.edu>, aschneider@utexas.edu (Astrid Schneider) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Marisol Smirnov Opinions expressed are solely my own and not those of NETCOM On-Line Communication Services. ------------------------------------------------------------ From bokonkwo@uu.net Fri Feb 02 03:45:41 1996 Path: ashpoly!cascade!bigsur!uu!bokonkwo From: bokonkwo@uu.net (Bill Okonkwo) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Feb02.034541.9608@uu.net> Date: Fri, 02 Feb 1996 03:45:41 GMT References: <1996Feb01.085841.3188@utexas.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Feb01.085841.3188@utexas.edu>, aschneider@utexas.edu (Astrid Schneider) 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. -- Bill Okonkwo *PLONK* filter active for trolls. PC-9821Ap2 (NEC) - NetBSD 1.0 From dgirard@purdue.edu Sun Feb 04 04:01:41 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!dgirard From: dgirard@purdue.edu (Dave Girard) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Feb04.040141.5218@purdue.edu> Date: Sun, 04 Feb 1996 04:01:41 GMT References: <1996Feb01.085841.3188@utexas.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Feb01.085841.3188@utexas.edu>, aschneider@utexas.edu (Astrid Schneider) 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. -- Dave Girard *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From fvasiliev@cmu.edu Tue Feb 06 02:06:41 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cmu!fvasiliev From: fvasiliev@cmu.edu (Fiona Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Feb06.020641.3650@cmu.edu> Date: Tue, 06 Feb 1996 02:06:41 GMT References: <1996Feb01.085841.3188@utexas.edu> <1996Feb04.040141.5218@purdue.edu> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Feb04.040141.5218@purdue.edu>, dgirard@purdue.edu (Dave Girard) 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. -- Fiona Vasiliev *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0