On Thursday 24 February 2005 01:33 pm, Mike Morris wrote:
> Hi,
>
> I'm wondering if anyone has any clever algorithms for performing 16 bit
> integer division by a constant using the multiply instruction in the 18F
> instruction set. I've looked over the many standard division routines, and
> thought perhaps there may be ones that employ the hardware multiply to
> really speed things up.
>
> Specifically, I need to scale a number (0 - 65535) to 0 - 2730 (hence a
> divide by 24.)  Maybe I'm missing a real obvious approach, but I'd
> appreciate any suggestions anyone might have.

Multiply by 2731 then shift right.
X = (value * 2731) >> 16;
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