>How would I replace this group of code with C18? This
>is a critical timing delay.
>
>        REPT    (INST_CYCLES_NEEDED - 3)
>        NOP
>        ENDM
>
>The program allows to specify the clock speed, which then
>adjusts the number of clock periods to get the desired delays.

The REPT operator looks like it is possibly a macro, which is probably 
defined in one of the include files. As a start, I would try trawling any 
likely looking include files (compiler.h?, any processor specific .h files?) 
and searching them with a text editor for 'rept' to see if a macro is 
#defined. You could then probably use the macro as is in your files.

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