#include <16F676.h>
#device adc=10 
#fuses INTRC_IONOWDTPUTNOPROTECTBROWNOUTNOMCLR
#use delay (clock=4000000) // 4MHz clock

#rom  0x3ff={0x3444}

#byte PORTA = 0x05
#byte PORTC = 0x07
#byte TRISA = 0x85
#byte TRISC = 0x87

#define SPORTA PORTA
#define SPORTC PORTC

#define  TICKS_BETWEEN_INTERRUPTS      5000 //5000
#define  INTERRUPT_OVERHEAD            35
#define  TMR1RESET (0xFFFF-(TICKS_BETWEEN_INTERRUPTS-INTERRUPT_OVERHEAD))

const char SegCode[11] = {0x400x570x220x060x150x0C0x080x560x000x040xFF};
   //                       0    1    2    3    4    5    6    7    8    9
const char Column[3]   = {0x020x010x04};
static char Segment[3] = {0x7f0x7f0x7f};   
static unsigned char ColCount=0x00;

void CPU_SETUP(void);
void Display(void);
void HTO7S(unsigned int32 Num);

byte i;
unsigned int32 result;

#INT_TIMER1
void Timer1(void)
{   
   set_timer1(TMR1RESET);
   Display();   
}   

void main()
{      
   unsigned char i;
   
   CPU_SETUP();
   
   while(true)
   {         
      result=0;
      for (i=0;i<20;i++)
      {
         set_adc_channel(3); 
         delay_ms(1); 
         result=result+read_adc();
      }
        //result = 0x3fe;                           
       HTO7S(result/20);   
      delay_ms(200);          
   }
   
}

void CPU_SETUP()
{
    
   setup_comparator(NC_NC_NC_NC);   // not use comparator module
   setup_adc_ports( sAN3 | VSS_VDD); 
   setup_adc(ADC_CLOCK_DIV_64);
   TRISA=0b00011000;
   PORTA=0x27;
   TRISC=0b00000000;
   PORTC=0x37;
   
   
   setup_timer_1(T1_INTERNAL|T1_DIV_BY_1);
   set_timer1(TMR1RESET);
   enable_interrupts(GLOBAL);
   enable_interrupts(INT_TIMER1);   
}

//-------------------------------------
// Display routine
//-------------------------------------
void Display()
{
   PORTA = 0b00100111;     // off all digits column and Segment G
   PORTC = 0b00111111;   // off segment a-f   
   delay_cycles(2);
   

   if (ColCount>=3) 
   ColCount=0;
       
   SPORTC = Segment[ColCount];
   SPORTA = ((Segment[ColCount] & 0b01000000)>>1) | (Column[ColCount]^0x07);
   ColCount++;            
}   

//--------------------------------------
// Convet HEX 2 byte to 7-Segment code
//--------------------------------------
void HTO7S(unsigned int32 Num)
{

   unsigned int32 res;

   
   Segment[0]=SegCode[30*Num/10230];
   if (Segment[0]==0x40) 
   Segment[0]=0xFF;
   
   res = 30*Num%10230;
   Segment[1]=SegCode[10*res/10230];
   res=10*res%10230;
   Segment[2]=SegCode[10*res/10230];
}