From hkim@uu.net Sun Jan 22 04:07:19 1995 Path: ashpoly!cascade!bigsur!uu!hkim From: hkim@uu.net (Hugo Kim) Newsgroups: comp.sys.m68k Subject: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan22.040719.5327@uu.net> Date: Sun, 22 Jan 1995 04:07:19 GMT Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! 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? -- Hugo Kim -- UUNET Technologies, Falls Church VA "A soul is not exclusive to biology." From mvasiliev@kiae.su Sun Jan 22 20:27:19 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!kiae!mvasiliev From: mvasiliev@kiae.su (Matthias Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan22.202719.7370@kiae.su> Date: Sun, 22 Jan 1995 20:27:19 GMT References: <1995Jan22.040719.5327@uu.net> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Jan22.040719.5327@uu.net>, hkim@uu.net (Hugo Kim) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > 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. -- Matthias Vasiliev "Do not worship the copy." Commodore Amiga 500 (1MB OCS) / System 7.5.1 From klarsson@tum.de Mon Jan 23 15:39:19 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!tum!klarsson From: klarsson@tum.de (Karen Larsson) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan23.153919.8769@tum.de> Date: Mon, 23 Jan 1995 15:39:19 GMT References: <1995Jan22.040719.5327@uu.net> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Jan22.040719.5327@uu.net>, hkim@uu.net (Hugo Kim) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. > 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! -- Karen Larsson "Hold for relay." Amiga 3000T / AmigaOS 3.1 From dsmirnov@cmu.edu Tue Jan 24 11:42:19 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cmu!dsmirnov From: dsmirnov@cmu.edu (Diego Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Observation: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan24.114219.7235@cmu.edu> Date: Tue, 24 Jan 1995 11:42:19 GMT References: <1995Jan22.040719.5327@uu.net> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1995Jan22.040719.5327@uu.net>, hkim@uu.net (Hugo Kim) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Diego Smirnov Zyxel U-1496E @ 9600 Telebit bps "Marcus is not one man."