From sgonzalez@illinois.edu Thu Sep 08 09:11:43 1994 Path: ashpoly!cascade!transat!ukc!fennimore!illinois!sgonzalez From: sgonzalez@illinois.edu (Seo-yeon González) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Sep08.091143.3310@illinois.edu> Date: Thu, 08 Sep 1994 09:11:43 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.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. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! 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? -- === Seo-yeon González === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "Tape doesn't lie at 02:14. Ears do." From nnovak@pipeline.com Thu Sep 08 17:39:43 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!pipeline!nnovak From: nnovak@pipeline.com (Nadia Novak) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Sep08.173943.7875@pipeline.com> Date: Thu, 08 Sep 1994 17:39:43 GMT References: <1994Sep08.091143.3310@illinois.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Sep08.091143.3310@illinois.edu>, sgonzalez@illinois.edu (Seo-yeon González) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Nadia Novak "We don't sign stars. We build them." 486DX2/66 (Linux 1.2.13) / NEXTSTEP 3.3 From kkang@ox.ac.uk Sat Sep 10 00:48:43 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!ox!kkang From: kkang@ox.ac.uk (Kenji Kang) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Sep10.004843.6499@ox.ac.uk> Date: Sat, 10 Sep 1994 00:48:43 GMT References: <1994Sep08.091143.3310@illinois.edu> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Sep08.091143.3310@illinois.edu>, sgonzalez@illinois.edu (Seo-yeon González) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Kenji Kang Tape trading list upon request. SASE required for international mail. From hlopez@illinois.edu Sun Sep 11 07:44:43 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!illinois!hlopez From: hlopez@illinois.edu (Hana López) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Sep11.074443.5108@illinois.edu> Date: Sun, 11 Sep 1994 07:44:43 GMT References: <1994Sep08.091143.3310@illinois.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 10 In article <1994Sep08.091143.3310@illinois.edu>, sgonzalez@illinois.edu (Seo-yeon González) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. > When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Hana López Zyxel U-1496E @ ISDN 64k bps "A soul is not exclusive to biology."