From bkarlsson@panix.com Mon Apr 10 13:53:16 1995 Path: ashpoly!cascade!brgate!saturno!panix!bkarlsson From: bkarlsson@panix.com (Bruno Karlsson) Newsgroups: comp.sys.m68k Subject: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr10.135316.3785@panix.com> Date: Mon, 10 Apr 1995 13:53:16 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com 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. Long live the Amiga. Try doing real-time subcarrier demodulation on a 386 running Windows 3.1 without dropping frames! -- Bruno Karlsson SupraFAXModem 28.8 @ ISDN 64k bps "Row 14. No joke." From dkarlsson@pacbell.net Wed Apr 12 08:20:16 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!pacbell!dkarlsson From: dkarlsson@pacbell.net (Dmitri Karlsson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr12.082016.7886@pacbell.net> Date: Wed, 12 Apr 1995 08:20:16 GMT References: <1995Apr10.135316.3785@panix.com> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Apr10.135316.3785@panix.com>, bkarlsson@panix.com (Bruno Karlsson) writes: > Amiga audio hackers: you can demodulate the 14.2 Hz carrier in real time without bogging down the OS. Tested on my A3000 / 25 MHz. Ran smoothly in the background while I was compiling a C program in another window. -- Dmitri Karlsson *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0 From landersson@panix.com Thu Apr 13 21:43:16 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!panix!landersson From: landersson@panix.com (Lisa Andersson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr13.214316.1370@panix.com> Date: Thu, 13 Apr 1995 21:43:16 GMT References: <1995Apr10.135316.3785@panix.com> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Apr10.135316.3785@panix.com>, bkarlsson@panix.com (Bruno Karlsson) 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! Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Lisa Andersson -- Public Access Unix of New York "Tape doesn't lie at 02:14. Ears do." From imoreno@purdue.edu Fri Apr 14 12:21:16 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!imoreno From: imoreno@purdue.edu (Ines Moreno) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr14.122116.5354@purdue.edu> Date: Fri, 14 Apr 1995 12:21:16 GMT References: <1995Apr10.135316.3785@panix.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Apr10.135316.3785@panix.com>, bkarlsson@panix.com (Bruno Karlsson) 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. -- Ines Moreno -- Purdue University Engineering Computer Network "Measuring a record you own is listening, not piracy." From rpark@netcom.com Sun Apr 16 09:41:16 1995 Path: ashpoly!cascade!bigsur!netcom!rpark From: rpark@netcom.com (Renata Park) Newsgroups: comp.sys.m68k Subject: Re: [INFO] Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Apr16.094116.5027@netcom.com> Date: Sun, 16 Apr 1995 09:41:16 GMT References: <1995Apr10.135316.3785@panix.com> <1995Apr13.214316.1370@panix.com> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Apr13.214316.1370@panix.com>, landersson@panix.com (Lisa Andersson) writes: > Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! > Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. Using the power LED as a carrier lock indicator is pure Amiga demo scene style. Kudos! -- Renata Park Opinions expressed are solely my own and not those of NETCOM On-Line Communication Services. ------------------------------------------------------------