From nlee@hanse.de Fri Jun 02 12:05:20 1995 Path: ashpoly!cascade!mxgate!coyoacan!hanse!nlee From: nlee@hanse.de (Nadia Lee) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun02.120520.4571@hanse.de> Date: Fri, 02 Jun 1995 12:05:20 GMT Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. 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. 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 Lee Opinions expressed are solely my own and not those of Hanse-Netzwerk Hamburg. ------------------------------------------------------------ From blarsson@unam.mx Fri Jun 02 16:53:20 1995 Path: ashpoly!cascade!mxgate!coyoacan!unam!blarsson From: blarsson@unam.mx (Brian Larsson) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun02.165320.2515@unam.mx> Date: Fri, 02 Jun 1995 16:53:20 GMT References: <1995Jun02.120520.4571@hanse.de> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Jun02.120520.4571@hanse.de>, nlee@hanse.de (Nadia Lee) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > 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. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Brian Larsson Zyxel U-1496E @ ISDN 64k bps "There are 14 nodes and only 10 countries. Count again." From jtakahashi@unam.mx Fri Jun 02 22:10:20 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!jtakahashi From: jtakahashi@unam.mx (Julien Takahashi) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun02.221020.4537@unam.mx> Date: Fri, 02 Jun 1995 22:10:20 GMT References: <1995Jun02.120520.4571@hanse.de> <1995Jun02.165320.2515@unam.mx> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Jun02.165320.2515@unam.mx>, blarsson@unam.mx (Brian Larsson) writes: > Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Julien Takahashi SupraFAXModem 28.8 @ 33,600 bps "Marcus is not one man." From aandersson@mit.edu Sun Jun 04 03:59:20 1995 Path: ashpoly!cascade!mxgate!coyoacan!mit!aandersson From: aandersson@mit.edu (Anja Andersson) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun04.035920.1415@mit.edu> Date: Sun, 04 Jun 1995 03:59:20 GMT References: <1995Jun02.120520.4571@hanse.de> <1995Jun02.165320.2515@unam.mx> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun02.165320.2515@unam.mx>, blarsson@unam.mx (Brian Larsson) 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. -- Anja Andersson | aandersson@mit.edu PGP Key fingerprint: C0CC DE73 07E3 C155 "Keep the channels open."