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Date: Fri, 11 Sep 2020 17:43:56 -0700
Subject: [AVR] Square on AVR?
Thread-Topic: [AVR] Square on AVR?
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Is it reasonable to calculate the square root of a 16 bit or preferably 20 =
bit integer?  I'll need to do this 400 times a second.  I do have an altern=
ate hardware plan that would work, but I'd prefer using the Square root.  I=
t's a PID controller and I'd rather use a "constant" (between calculations =
at least) Voltage output, or I can use a fet to do PWM without the math (wi=
th square root I'd calculate the power required, take the square root and s=
et the voltage output to that value).  This would reduce the noise from the=
 high power (240W) switching converter.  Alternately I could set a fixed ma=
x voltage and drive a fet with a pwm signal.  Just wondering how expensive =
that calculation would be in terms of processor cycles.


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