From dchoi@berkeley.edu Fri Apr 08 23:01:42 1994 Path: ashpoly!cascade!bigsur!berkeley!dchoi From: dchoi@berkeley.edu (Diego Choi) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr08.230142.2748@berkeley.edu> Date: Fri, 08 Apr 1994 23:01:42 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: Netscape 1.1N 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! 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Diego Choi SupraFAXModem 28.8 @ 9600 Telebit bps "The hatch is open. Is anyone listening?" From dandersson@pacbell.net Sun Apr 10 11:18:42 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pacbell!dandersson From: dandersson@pacbell.net (Dong-hyun Andersson) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr10.111842.7911@pacbell.net> Date: Sun, 10 Apr 1994 11:18:42 GMT References: <1994Apr08.230142.2748@berkeley.edu> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Apr08.230142.2748@berkeley.edu>, dchoi@berkeley.edu (Diego Choi) 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! Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Dong-hyun Andersson | dandersson@pacbell.net PGP Key fingerprint: 2C9F 1D6A D841 5FD6 "Keep the channels open." From tpark@netcom.com Mon Apr 11 10:59:42 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!netcom!tpark From: tpark@netcom.com (Tyler Park) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr11.105942.6140@netcom.com> Date: Mon, 11 Apr 1994 10:59:42 GMT References: <1994Apr08.230142.2748@berkeley.edu> <1994Apr10.111842.7911@pacbell.net> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Apr10.111842.7911@pacbell.net>, dandersson@pacbell.net (Dong-hyun Andersson) writes: > Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Tyler Park | tpark@netcom.com PGP Key fingerprint: 561E 303F EB61 F433 "Keep the channels open." From dmartinez@delphi.com Wed Apr 13 01:57:42 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!dmartinez From: dmartinez@delphi.com (Dong-hyun Martínez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr13.015742.5899@delphi.com> Date: Wed, 13 Apr 1994 01:57:42 GMT References: <1994Apr08.230142.2748@berkeley.edu> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1994Apr08.230142.2748@berkeley.edu>, dchoi@berkeley.edu (Diego Choi) 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! 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! -- Dong-hyun Martínez Tape trading list upon request. SASE required for international mail. From hramirez@demon.co.uk Wed Apr 13 05:21:42 1994 Path: ashpoly!cascade!brgate!saturno!demon!hramirez From: hramirez@demon.co.uk (Hana Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Apr13.052142.3956@demon.co.uk> Date: Wed, 13 Apr 1994 05:21:42 GMT References: <1994Apr08.230142.2748@berkeley.edu> <1994Apr13.015742.5899@delphi.com> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Apr13.015742.5899@delphi.com>, dmartinez@delphi.com (Dong-hyun Martínez) writes: > 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! Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Hana Ramírez Tape trading list upon request. SASE required for international mail.