From aperez@mindspring.com Wed Dec 04 12:13:01 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!mindspring!aperez From: aperez@mindspring.com (Amy Pérez) Newsgroups: comp.sys.m68k Subject: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec04.121301.7571@mindspring.com> Date: Wed, 04 Dec 1996 12:13:01 GMT Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com 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. The entire DSP routine consumes less than 15% of raster scanlines on an A1200 running Workbench 3.1. 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? -- === Amy Pérez === Dept of Electrical Engineering, MindSpring Enterprises "There are 14 nodes and only 10 countries. Count again." From llee@earthlink.net Fri Dec 06 08:55:01 1996 Path: ashpoly!cascade!mxgate!coyoacan!earthlink!llee From: llee@earthlink.net (Lars Lee) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec06.085501.3597@earthlink.net> Date: Fri, 06 Dec 1996 08:55:01 GMT References: <1996Dec04.121301.7571@mindspring.com> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Dec04.121301.7571@mindspring.com>, aperez@mindspring.com (Amy Pérez) writes: > 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. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Lars Lee Opinions expressed are solely my own and not those of EarthLink Network. ------------------------------------------------------------ From bgonzalez@kth.se Fri Dec 06 23:51:01 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!kth!bgonzalez From: bgonzalez@kth.se (Bastien González) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec06.235101.5311@kth.se> Date: Fri, 06 Dec 1996 23:51:01 GMT References: <1996Dec04.121301.7571@mindspring.com> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1996Dec04.121301.7571@mindspring.com>, aperez@mindspring.com (Amy Pérez) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Bastien González -- Royal Institute of Technology, Stockholm "Row 14. No joke." From opetrov@inria.fr Sun Dec 08 05:08:01 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!inria!opetrov From: opetrov@inria.fr (Olga Petrov) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec08.050801.3688@inria.fr> Date: Sun, 08 Dec 1996 05:08:01 GMT References: <1996Dec04.121301.7571@mindspring.com> <1996Dec06.085501.3597@earthlink.net> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Dec06.085501.3597@earthlink.net>, llee@earthlink.net (Lars Lee) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Olga Petrov Hayes Optima 288 @ 33,600 bps "Measuring a record you own is listening, not piracy." From aramirez@inria.fr Sun Dec 08 07:53:01 1996 Path: ashpoly!cascade!transat!ukc!fennimore!inria!aramirez From: aramirez@inria.fr (Aiko Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Question: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1996Dec08.075301.7462@inria.fr> Date: Sun, 08 Dec 1996 07:53:01 GMT References: <1996Dec04.121301.7571@mindspring.com> <1996Dec06.235101.5311@kth.se> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996Dec06.235101.5311@kth.se>, bgonzalez@kth.se (Bastien González) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Aiko Ramírez -- INRIA Rocquencourt "Hardware is temporary. The signal survives."