From nlarsson@mindspring.com Tue Jul 05 10:36:50 1994 Path: ashpoly!cascade!bigsur!mindspring!nlarsson From: nlarsson@mindspring.com (Nadia Larsson) Newsgroups: comp.sys.m68k Subject: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul05.103650.6391@mindspring.com> Date: Tue, 05 Jul 1994 10:36:50 GMT Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: WinVN 0.99.5 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Nadia Larsson SupraFAXModem 28.8 @ 19,200 bps "They will send a copy in my place." From hgarcia@panix.com Wed Jul 06 20:05:50 1994 Path: ashpoly!cascade!mxgate!coyoacan!panix!hgarcia From: hgarcia@panix.com (Heather García) Newsgroups: comp.sys.m68k Subject: Re: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul06.200550.8924@panix.com> Date: Wed, 06 Jul 1994 20:05:50 GMT References: <1994Jul05.103650.6391@mindspring.com> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1994Jul05.103650.6391@mindspring.com>, nlarsson@mindspring.com (Nadia Larsson) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. PGP Public key available via finger or upon request. -- Heather García *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0 From sperez@unam.mx Fri Jul 08 19:53:50 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!unam!sperez From: sperez@unam.mx (Seo-yeon Pérez) Newsgroups: comp.sys.m68k Subject: Re: Data: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Jul08.195350.1140@unam.mx> Date: Fri, 08 Jul 1994 19:53:50 GMT References: <1994Jul05.103650.6391@mindspring.com> <1994Jul06.200550.8924@panix.com> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: Netscape 1.1N Lines: 10 In article <1994Jul06.200550.8924@panix.com>, hgarcia@panix.com (Heather García) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. > PGP Public key available via finger or upon request. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Seo-yeon Pérez *PLONK* filter active for trolls. NeXTstation Turbo Color - NetBSD 1.0