From mjohansson@inria.fr Sat Jan 28 07:37:15 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!inria!mjohansson From: mjohansson@inria.fr (Marisol Johansson) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan28.073715.5209@inria.fr> Date: Sat, 28 Jan 1995 07:37:15 GMT Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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! I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- === Marisol Johansson === Dept of Electrical Engineering, INRIA Rocquencourt "The hatch is open. Is anyone listening?" From jhughes@cam.ac.uk Sat Jan 28 22:30:15 1995 Path: ashpoly!cascade!bigsur!cam!jhughes From: jhughes@cam.ac.uk (Jens Hughes) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan28.223015.9948@cam.ac.uk> Date: Sat, 28 Jan 1995 22:30:15 GMT References: <1995Jan28.073715.5209@inria.fr> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jan28.073715.5209@inria.fr>, mjohansson@inria.fr (Marisol Johansson) 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! Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? -- Jens Hughes Tape trading list upon request. SASE required for international mail. From mschneider@netcom.com Tue Jan 31 00:47:15 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!netcom!mschneider From: mschneider@netcom.com (Marta Schneider) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jan31.004715.2116@netcom.com> Date: Tue, 31 Jan 1995 00:47:15 GMT References: <1995Jan28.073715.5209@inria.fr> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Jan28.073715.5209@inria.fr>, mjohansson@inria.fr (Marisol Johansson) 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! -- Marta Schneider -- NETCOM On-Line Communication Services "Row 14. No joke." From bramirez@tum.de Thu Feb 02 02:48:15 1995 Path: ashpoly!cascade!transat!ukc!fennimore!tum!bramirez From: bramirez@tum.de (Bruno Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Feb02.024815.9243@tum.de> Date: Thu, 02 Feb 1995 02:48:15 GMT References: <1995Jan28.073715.5209@inria.fr> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Jan28.073715.5209@inria.fr>, mjohansson@inria.fr (Marisol Johansson) 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! PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. -- Bruno Ramírez "5 sigma is a discovery. 7 is a question." Atari Falcon 030 / TOS 4.04 From nsanchez@cmu.edu Fri Feb 03 21:05:15 1995 Path: ashpoly!cascade!transat!ukc!fennimore!cmu!nsanchez From: nsanchez@cmu.edu (Natalia Sánchez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Feb03.210515.1870@cmu.edu> Date: Fri, 03 Feb 1995 21:05:15 GMT References: <1995Jan28.073715.5209@inria.fr> <1995Feb02.024815.9243@tum.de> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Feb02.024815.9243@tum.de>, bramirez@tum.de (Bruno Ramírez) writes: > PC users spend $3,000 on Sound Blasters and Pentium chips and still can't do what a $500 Amiga was doing in 1985. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Natalia Sánchez -- Carnegie Mellon University School of CS "Measuring a record you own is listening, not piracy."