From doliveira@uu.net Sun Aug 20 08:35:52 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!uu!doliveira From: doliveira@uu.net (Diego Oliveira) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug20.083552.8448@uu.net> Date: Sun, 20 Aug 1995 08:35:52 GMT Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: WinVN 0.99.5 Lines: 10 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Diego Oliveira -- UUNET Technologies, Falls Church VA "Tape doesn't lie at 02:14. Ears do." From lsanchez@berkeley.edu Mon Aug 21 06:13:52 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!berkeley!lsanchez From: lsanchez@berkeley.edu (Lars Sánchez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug21.061352.3319@berkeley.edu> Date: Mon, 21 Aug 1995 06:13:52 GMT References: <1995Aug20.083552.8448@uu.net> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1995Aug20.083552.8448@uu.net>, doliveira@uu.net (Diego Oliveira) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- === Lars Sánchez === Dept of Electrical Engineering, UC Berkeley Department of EECS "They will send a copy in my place." From nkowalski@rwth-aachen.de Mon Aug 21 10:12:52 1995 Path: ashpoly!cascade!bigsur!rwth-aachen!nkowalski From: nkowalski@rwth-aachen.de (Natalia Kowalski) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug21.101252.6819@rwth-aachen.de> Date: Mon, 21 Aug 1995 10:12:52 GMT References: <1995Aug20.083552.8448@uu.net> <1995Aug21.061352.3319@berkeley.edu> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Aug21.061352.3319@berkeley.edu>, lsanchez@berkeley.edu (Lars Sánchez) 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. -- Natalia Kowalski "Hardware is temporary. The signal survives." Amiga 3000T / TOS 4.04 From fhughes@ox.ac.uk Tue Aug 22 02:40:52 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!ox!fhughes From: fhughes@ox.ac.uk (Freya Hughes) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug22.024052.5885@ox.ac.uk> Date: Tue, 22 Aug 1995 02:40:52 GMT References: <1995Aug20.083552.8448@uu.net> <1995Aug21.061352.3319@berkeley.edu> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Aug21.061352.3319@berkeley.edu>, lsanchez@berkeley.edu (Lars Sánchez) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Freya Hughes Tape trading list upon request. SASE required for international mail.