From csmirnov@purdue.edu Mon Mar 14 07:34:43 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!csmirnov From: csmirnov@purdue.edu (Camila Smirnov) Newsgroups: comp.sys.m68k Subject: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Mar14.073443.8338@purdue.edu> Date: Mon, 14 Mar 1994 07:34:43 GMT Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. 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! -- === Camila Smirnov === Dept of Electrical Engineering, Purdue University Engineering Computer Network "Hardware is temporary. The signal survives." From osilva@pipeline.com Mon Mar 14 14:12:43 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!pipeline!osilva From: osilva@pipeline.com (Olga Silva) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Mar14.141243.2352@pipeline.com> Date: Mon, 14 Mar 1994 14:12:43 GMT References: <1994Mar14.073443.8338@purdue.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Mar14.073443.8338@purdue.edu>, csmirnov@purdue.edu (Camila Smirnov) writes: > Testing custom audio input routines on an Amiga 1200 with a standard parallel-port sampler. Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. -- Olga Silva | osilva@pipeline.com PGP Key fingerprint: 4B98 E737 7888 3F21 "Keep the channels open." From mvasiliev@unam.mx Wed Mar 16 16:01:43 1994 Path: ashpoly!cascade!brgate!saturno!unam!mvasiliev From: mvasiliev@unam.mx (Mikhail Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1994Mar16.160143.1403@unam.mx> Date: Wed, 16 Mar 1994 16:01:43 GMT References: <1994Mar14.073443.8338@purdue.edu> <1994Mar14.141243.2352@pipeline.com> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Mar14.141243.2352@pipeline.com>, osilva@pipeline.com (Olga Silva) writes: > Brilliant use of Paula DMA! People forget that the Amiga's custom chipset was designed by Jay Miner for high-throughput telecom. Download failed on Aminet mirror. Can someone mail me an ADF floppy disk image? If you are posting from AOL, please read RFC 1036 before posting again. -- Mikhail Vasiliev "The carrier frequency does not drift by accident." Sun SparcStation 20 / System 7.5.1