How to avoid DIV32 command?

[cncmachineguy]

var=1120000/freq
reload=(65535-var)+8

"freq" variable range is between 10 and 1200.

Couple questions:
when freq = 10, var = 112000 so:
reload = -46457

This is ok?

Next question:
Assuming freq comes from A/D, seems like there should be a way to "scale" the A/D to get your reload value. What is the reload span? for instance,
freq = 10, reload = ??
freq = 1200, reload = ??

are the answers -46457 and 64609?