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Date: Thu, 2 Jan 2014 21:53:02 -0800
From: Larry Doolittle <ldoolitt AT recycle DOT lbl DOT gov>
To: geda-user AT delorie DOT com
Subject: Re: [geda-user] Help sending a sine wave to a speaker
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Friends -

On Fri, Jan 03, 2014 at 04:37:41AM +0100, Peter Stuge wrote:
> Rob Butts wrote:
> > I use a microchip pic16f1825 to read a byte from an eeprom via spi
> > and send it to a dac and ultimately to a speaker.
> If you want to use sin in production maybe you should go for a
> precalculated lookup table.

On fixed-point and/or small microprocessors, a CORDIC will
often win over the generic libc sin().  If you know the accuracy
you need, you can tune the number of stages.  On a strongarm,
I once saved a factor of 1000 in CPU time.

The table-based approach is sometimes useful, but not as general.

  - Larry