PIC16F914 outputs adjustable duty cycle PWM waveform

#include
typedef unsigned int uint;
typedef unsigned char uchar;
#define KEY0_DOWN() (RB4==0)//define key pressed
__CONFIG(0X1014);//internal clock
uchar KEY0_FLAG=0;
/*****************************/ 
//OSC SET; INTER 4MHZ PERIOD 1US
/*****************************/ 
void OSC_INIT()
{
  OSCCON=0X67;//set internal clock 4MHZ
}
/*****************************/ 
//DELAY FUNCTION();
/*****************************/ 
void delay(uint z)
{
   uint x,y;
   for(x=z;x>0;x--)
     for(y=110;y>0;y--);
}
/*************************/ 
//GPIO SET;
/*****************************/ 

void GPIO_INIT()
{
  TRISC5=0;//RC5 SET PWM OUT;
  TRISD2=0;//RD2 SET PWM OUT;
  RC5=RD2=0;
  TRISB4=1;
  IOCB4=1;//Enable RB4 level change interrupt
  WPUB=0X10;//Enable pull-up
  RBIE=1;
  RBIF=0;
  PEIE=1;
  GIE=1;
}
/*************************/ 
//PWM MODEL INIT;
/*************************/ 
void PWM_INIT()
{
  CCP1CON=0B00001100;//PWM mode
  CCP2CON=0B00001100;//PWM mode
  T2CKPS1=1;
  PR2=155;//PWM period = [PR2+1]*4*TOSC*T2 pre-division value, so PWM frequency = 1/period = 400HZ
  TMR2ON=1;
  CCPR1L=0;//Duty cycle = CCPR1L:CCP1CON<5:4>/4(PR2+1);
  CCPR2L=0;//Duty cycle = CCPR2L:CCP2CON<5:4>/4(PR2+1);
}
void main()
{
  GPIO_INIT();
  PWM_INIT();
  while(1);//Initialization is complete and waiting for interrupt response is OK
}  

//Interrupt response entry
void interrupt ALL_ISR()//Output 10%-100% duty cycle PWM waveform
{
  if(RBIF)
    {
     delay(5);
     if(KEY0_DOWN())
        {
            KEY0_FLAG++;
            if(KEY0_FLAG==11)KEY0_FLAG=0;
        }
     switch(KEY0_FLAG)
          {
             case 0:CCPR1L=CCPR2L=0;break;
             case 1:CCPR1L=CCPR2L=16;break;
             case break; case 10:CCPR1L=CCPR2L=156              ;
             break
             ;              default              :              break              ;              }           RBIF        =0              ;    } }