How to calculate CCPR1L in varying data?

and also,
CCPR1L contains the upper 8 bits of the 10 bit Duty Cycle value CCP1CON<5:4> contain the lower 2 bits
How to divide the 8 bits and 2 bits in calculation?

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I have formula and i got a pwm in standard data but i am confused,about automatic calculation in program?

I am using Hi-tech c compiler.

 

Take a look at the "Compiled Tips ‘N Tricks Guide" found here http://forum.allaboutcircuits.com/showthread.php?t=44852 section 3-14 should help you out. In order to get help. I think you need to show some code and tell us more about why and how you struggle