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PIC16f877 PWM doubt in resolution

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ragav4456

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Hi friends

I need to vary pwm duty cycle in 0 to 255(50khz). but 50khz resolution is 8.64 bits(0 to 398).

i need scale the value 0 to 398 into 0 to 255? How to scale the values?

input data 255=398/1.56 ;

correct or not? how to use float value?
____________________
Hitech C compiler
 

You'll preferably want to reduce the problem to a multiply with an integer factor and a right shift. E.g x*164 >> 8
 

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could you please check the format

CCPR1L= (x*164)>>8
Value=x%4;
Value=Value<<4;
CCP1CON= 0b00001100 | Value;

164 means?
x=input data(0 to 255)? correct or not?
 

x must have an unsigned int16 type, otherwise you'll get an overflow in the multiplication.

164 means?
x=input data(0 to 255)? correct or not?
The input value x is assumed with a range of 0 to 398, as asked in your post. I suggest to check the method yourself by putting in different values.
 

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