> Well, it really depends on what you are doing. Sometimes integer
    > routines can be used with fixed point data, but not as often as you
    > would like.

    Oh, and why not?  Fixed point numbers ARE integers.

You have to do things different on multiply and divide so that the "point"
stays in a fixed place.  Say you have 8 bits of fraction and 8 bits of
integer, so 1.5 is 0x0180.  An integer multiple of 0x180*0x180 would give
you 24000 - an overflow in integer arithmetic but NOT for fixed point.  In
this case you want the MIDDLE bits: 0x0240 is 2.25  (the bottom bits are
fractions of fractions, and not so significant.)

(I assume that's what Olin meant by "normalize", but I wanted to spell it
all out.)

BillW

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