32 bit square root

[Charles Linquis]

Thanks! I'm at the point where a hundred cycles makes the difference whether my ISR gets messed up or not.

[Acetronics2]

Hi, Charles

Did you see that one ???

http://www.piclist.com/techref/micro...qrt/sqrt32.htm

Alain

[Charles Linquis]

No, I missed that one. I'll give it a try.
I'm calculating the RMS currents of several non-sinusoidal waveforms simultaneously, along with checking limits and times, and sending the results on to another PIC for display and data collection. I have to sample frequently to get enough accuracy, and I have to do everything on a cycle-by-cycle basis.

[Charles Linquis]

I see that the 'movfp' instruction is used in the example. I'm not familiar with the 16F or 17F parts. Is that instruction equivalent to the 18F instruction 'movf' ?

[Acetronics2]

Hi, Charles

it's just a particular Movf for PIC 17 ...


from f : Register file address (00h to FFh)
to p : Peripheral register file address (00h to 1Fh)

I do not see any warning to use a simple " Movf " with a 18F Device ... ( banking may be ??? )

Alain