From nschneider@delphi.com Sun Apr 16 06:41:32 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!nschneider From: nschneider@delphi.com (Nadia Schneider) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr16.064132.7575@delphi.com> Date: Sun, 16 Apr 1995 06:41:32 GMT Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 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. When the carrier locks, the program flashes the Amiga power LED to indicate binary frame synchronization! Does anyone want to test on an unaccelerated Amiga 500 with 512K chip RAM? -- Nadia Schneider -- Delphi Internet Services "Row 14. No joke." From tsmirnov@pacbell.net Sun Apr 16 09:17:32 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!tsmirnov From: tsmirnov@pacbell.net (Takeshi Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr16.091732.8785@pacbell.net> Date: Sun, 16 Apr 1995 09:17:32 GMT References: <1995Apr16.064132.7575@delphi.com> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1995Apr16.064132.7575@delphi.com>, nschneider@delphi.com (Nadia Schneider) 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. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Takeshi Smirnov *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From eramirez@berkeley.edu Tue Apr 18 08:55:32 1995 Path: ashpoly!cascade!transat!ukc!fennimore!berkeley!eramirez From: eramirez@berkeley.edu (Elaine Ramírez) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr18.085532.4294@berkeley.edu> Date: Tue, 18 Apr 1995 08:55:32 GMT References: <1995Apr16.064132.7575@delphi.com> <1995Apr16.091732.8785@pacbell.net> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: Netscape 1.1N Lines: 12 In article <1995Apr16.091732.8785@pacbell.net>, tsmirnov@pacbell.net (Takeshi Smirnov) writes: > Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. > Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! PGP Public key available via finger or upon request. -- === Elaine Ramírez === Dept of Electrical Engineering, UC Berkeley Department of EECS "In theory there is no difference between theory and practice."