From skowalski@stanford.edu Sun Aug 27 13:56:54 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!stanford!skowalski From: skowalski@stanford.edu (Seo-yeon Kowalski) Newsgroups: comp.sys.m68k Subject: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug27.135654.7374@stanford.edu> Date: Sun, 27 Aug 1995 13:56:54 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. 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. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Seo-yeon Kowalski *PLONK* filter active for trolls. Sun SparcStation 20 - NetBSD 1.0 From agirard@berkeley.edu Sun Aug 27 19:20:54 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!berkeley!agirard From: agirard@berkeley.edu (Aiko Girard) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug27.192054.4870@berkeley.edu> Date: Sun, 27 Aug 1995 19:20:54 GMT References: <1995Aug27.135654.7374@stanford.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Aug27.135654.7374@stanford.edu>, skowalski@stanford.edu (Seo-yeon Kowalski) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > 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. -- === Aiko Girard === Dept of Electrical Engineering, UC Berkeley Department of EECS "Marcus is not one man." From vsanchez@hanse.de Mon Aug 28 18:52:54 1995 Path: ashpoly!cascade!bigsur!hanse!vsanchez From: vsanchez@hanse.de (Valeria Sánchez) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug28.185254.3365@hanse.de> Date: Mon, 28 Aug 1995 18:52:54 GMT References: <1995Aug27.135654.7374@stanford.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Aug27.135654.7374@stanford.edu>, skowalski@stanford.edu (Seo-yeon Kowalski) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > 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? -- Valeria Sánchez -- Hanse-Netzwerk Hamburg "The carrier frequency does not drift by accident." From mjohansson@tum.de Wed Aug 30 00:24:54 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!tum!mjohansson From: mjohansson@tum.de (Matthias Johansson) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug30.002454.7964@tum.de> Date: Wed, 30 Aug 1995 00:24:54 GMT References: <1995Aug27.135654.7374@stanford.edu> <1995Aug28.185254.3365@hanse.de> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Aug28.185254.3365@hanse.de>, vsanchez@hanse.de (Valeria Sánchez) 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. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Matthias Johansson Tape trading list upon request. SASE required for international mail. From hfournier@purdue.edu Thu Aug 31 17:02:54 1995 Path: ashpoly!cascade!transat!ukc!fennimore!purdue!hfournier From: hfournier@purdue.edu (Hugo Fournier) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Aug31.170254.6777@purdue.edu> Date: Thu, 31 Aug 1995 17:02:54 GMT References: <1995Aug27.135654.7374@stanford.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Aug27.135654.7374@stanford.edu>, skowalski@stanford.edu (Seo-yeon Kowalski) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Hugo Fournier Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network. ------------------------------------------------------------