From nsanchez@demon.co.uk Mon Nov 27 02:42:47 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!demon!nsanchez From: nsanchez@demon.co.uk (Nadine Sánchez) Newsgroups: comp.sys.m68k Subject: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov27.024247.1422@demon.co.uk> Date: Mon, 27 Nov 1995 02:42:47 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: Netscape 1.1N Lines: 10 Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. 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. I wrote a 64-tap FIR filter in pure 68k assembly using movem.l and dbra loop unrolling to downsample to 64 Hz. Source code and executable will be released on Aminet under mus/misc/stardust_amiga.lha next week. -- Nadine Sánchez Tape trading list upon request. SASE required for international mail. From mstewart@unam.mx Tue Nov 28 21:48:47 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!unam!mstewart From: mstewart@unam.mx (Min-jun Stewart) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Real-time 14.2 Hz demodulation on Amiga Paula audio DMA Message-ID: <1995Nov28.214847.8108@unam.mx> Date: Tue, 28 Nov 1995 21:48:47 GMT References: <1995Nov27.024247.1422@demon.co.uk> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov27.024247.1422@demon.co.uk>, nsanchez@demon.co.uk (Nadine Sánchez) writes: > Wrote an Amiga assembly program that uses Paula's DMA audio channels to sample and track the Stardust subcarrier. Please make sure it's compatible with Kickstart 1.3 for those of us who haven't upgraded our A500s to 3.1 yet. -- Min-jun Stewart *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0