I am not sure whats included inside of the 'Initialize_Encoders();' function, but I believe that you need to initialize the interrupts first by running function 'Initialize_Interrupts();' before you run 'Initialize_Encoders();' inside of function 'User_Initialization()', like so:
Code:
void User_Initialization (void)
{
...
Initialize_Interrupts();
Initialize_Encoders();
Putdata(&txdata); /* DO NOT CHANGE! */
...
}