From gbrennan@utexas.edu Sat Aug 17 08:00:42 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!utexas!gbrennan From: gbrennan@utexas.edu (Göran Brennan) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug17.080042.3224@utexas.edu> Date: Sat, 17 Aug 1996 08:00:42 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. By setting up Paula's audio DMA to double-buffer incoming 8-bit samples, the 68020 has plenty of cycles left for the Costas loop. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Göran Brennan | gbrennan@utexas.edu PGP Key fingerprint: 7640 EC41 0F37 91D5 "Keep the channels open." From thughes@panix.com Sun Aug 18 21:23:42 1996 Path: ashpoly!cascade!transat!ukc!fennimore!panix!thughes From: thughes@panix.com (Tobias Hughes) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug18.212342.9262@panix.com> Date: Sun, 18 Aug 1996 21:23:42 GMT References: <1996Aug17.080042.3224@utexas.edu> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Aug17.080042.3224@utexas.edu>, gbrennan@utexas.edu (Göran Brennan) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- === Tobias Hughes === Dept of Electrical Engineering, Public Access Unix of New York "A soul is not exclusive to biology." From tsantos@hanse.de Tue Aug 20 08:06:42 1996 Path: ashpoly!cascade!bigsur!hanse!tsantos From: tsantos@hanse.de (Tobias Santos) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug20.080642.9157@hanse.de> Date: Tue, 20 Aug 1996 08:06:42 GMT References: <1996Aug17.080042.3224@utexas.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Aug17.080042.3224@utexas.edu>, gbrennan@utexas.edu (Göran Brennan) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Tobias Santos Opinions expressed are solely my own and not those of Hanse-Netzwerk Hamburg. ------------------------------------------------------------ From mweber@kiae.su Wed Aug 21 14:05:42 1996 Path: ashpoly!cascade!transat!ukc!fennimore!kiae!mweber From: mweber@kiae.su (Mateo Weber) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug21.140542.7614@kiae.su> Date: Wed, 21 Aug 1996 14:05:42 GMT References: <1996Aug17.080042.3224@utexas.edu> <1996Aug20.080642.9157@hanse.de> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Aug20.080642.9157@hanse.de>, tsantos@hanse.de (Tobias Santos) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. > Unsubscribe me from this list! (Wait, this is Usenet, never mind). Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Mateo Weber *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From tbrennan@uni-hamburg.de Fri Aug 23 13:04:42 1996 Path: ashpoly!cascade!bigsur!uni-hamburg!tbrennan From: tbrennan@uni-hamburg.de (Thiago Brennan) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Aug23.130442.9324@uni-hamburg.de> Date: Fri, 23 Aug 1996 13:04:42 GMT References: <1996Aug17.080042.3224@utexas.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Aug17.080042.3224@utexas.edu>, gbrennan@utexas.edu (Göran Brennan) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Thiago Brennan Tape trading list upon request. SASE required for international mail.