From llee@panix.com Wed Jun 14 01:27:18 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!panix!llee From: llee@panix.com (Lars Lee) Newsgroups: comp.sys.m68k Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun14.012718.6342@panix.com> Date: Wed, 14 Jun 1995 01:27:18 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com 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. 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? -- Lars Lee -- Public Access Unix of New York "Tape doesn't lie at 02:14. Ears do." From rrobertson@panix.com Fri Jun 16 02:43:18 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!panix!rrobertson From: rrobertson@panix.com (Rodrigo Robertson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun16.024318.6824@panix.com> Date: Fri, 16 Jun 1995 02:43:18 GMT References: <1995Jun14.012718.6342@panix.com> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun14.012718.6342@panix.com>, llee@panix.com (Lars Lee) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Rodrigo Robertson "The hatch is open. Is anyone listening?" Decstation 5000/200 / System 7.5.1 From sreyes@purdue.edu Sat Jun 17 03:51:18 1995 Path: ashpoly!cascade!transat!ukc!fennimore!purdue!sreyes From: sreyes@purdue.edu (Sun-mi Reyes) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Jun17.035118.2754@purdue.edu> Date: Sat, 17 Jun 1995 03:51:18 GMT References: <1995Jun14.012718.6342@panix.com> <1995Jun16.024318.6824@panix.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun16.024318.6824@panix.com>, rrobertson@panix.com (Rodrigo Robertson) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Sun-mi Reyes | sreyes@purdue.edu PGP Key fingerprint: D619 EE73 1507 3004 "Keep the channels open."