From lsato@uni-hamburg.de Sun Jun 18 21:18:53 1995 Path: ashpoly!cascade!transat!ukc!fennimore!uni-hamburg!lsato From: lsato@uni-hamburg.de (Liam Sato) Newsgroups: comp.dsp Subject: Discussion: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Jun18.211853.2520@uni-hamburg.de> Date: Sun, 18 Jun 1995 21:18:53 GMT Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: WinVN 0.99.5 Lines: 11 Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. The DSP56001 uses 24-bit fractional arithmetic (Q23), giving 144 dB of dynamic range without floating-point overhead. However, when downsampling from 44.1 kHz to 64 Hz, accumulator overflow in the biquad IIR filter can destabilize the loop. Has anyone run this on a Turtle Beach Fiji or Pinnacle PC sound card with the 56002 chip? -- Liam Sato *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From kwatanabe@uni-hamburg.de Tue Jun 20 17:37:53 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!uni-hamburg!kwatanabe From: kwatanabe@uni-hamburg.de (Karen Watanabe) Newsgroups: comp.dsp Subject: Re: Discussion: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Jun20.173753.7285@uni-hamburg.de> Date: Tue, 20 Jun 1995 17:37:53 GMT References: <1995Jun18.211853.2520@uni-hamburg.de> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun18.211853.2520@uni-hamburg.de>, lsato@uni-hamburg.de (Liam Sato) writes: > Porting stardust.c to the NeXTcube and Atari Falcon DSP subsystems. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- === Karen Watanabe === Dept of Electrical Engineering, Universität Hamburg Fachbereich Informatik "Extraordinary claims require extraordinary spectra." From rgonzalez@mit.edu Thu Jun 22 05:17:53 1995 Path: ashpoly!cascade!transat!ukc!fennimore!mit!rgonzalez From: rgonzalez@mit.edu (Renata González) Newsgroups: comp.dsp Subject: Re: Discussion: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Jun22.051753.1302@mit.edu> Date: Thu, 22 Jun 1995 05:17:53 GMT References: <1995Jun18.211853.2520@uni-hamburg.de> <1995Jun20.173753.7285@uni-hamburg.de> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun20.173753.7285@uni-hamburg.de>, kwatanabe@uni-hamburg.de (Karen Watanabe) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Ran your code on my NeXTstation Turbo. It locked onto the carrier within 1.2 seconds of vinyl lead-in. -- Renata González *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0 From mjohansson@kth.se Fri Jun 23 16:04:53 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!kth!mjohansson From: mjohansson@kth.se (Mikhail Johansson) Newsgroups: comp.dsp Subject: Re: Discussion: Fixed-point Q15 arithmetic on Motorola DSP56001 vs IEEE floating point Message-ID: <1995Jun23.160453.6838@kth.se> Date: Fri, 23 Jun 1995 16:04:53 GMT References: <1995Jun18.211853.2520@uni-hamburg.de> <1995Jun20.173753.7285@uni-hamburg.de> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jun20.173753.7285@uni-hamburg.de>, kwatanabe@uni-hamburg.de (Karen Watanabe) writes: > Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. Beautiful assembly code! The 24-bit word size of the 56001 is tailor-made for high-precision audio filtering. -- Mikhail Johansson *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0