#include <xc.h>    //Use this to include the device header for your PIC.
                    //In our case, this will include pic16f690.h.
                    //Do not directly include pic16f690.h to avoid issues if you
                    //change your device later on. Always use <htc.h>.

#define _XTAL_FREQ 4000000  //4MHz, which is default
                            //This is used by the compiler to calculate how many
                            //instructions to delay in the calls to __delay_ms().


//set the configuration bits: internal OSC, everything off except MCLR
#pragma config FOSC=INTRCIO, WDTE=OFF, PWRTE=OFF, MCLRE=ON, CP=OFF, \
                CPD=OFF, BOREN=OFF, IESO=OFF, FCMEN=OFF

int main()
{
    TRISA = 0xFF;   //set all digital I/O to inputs
    TRISB = 0xFF;
    TRISC = 0xFF;

    ANSEL = 0x00;   //disable all analog ports
    ANSELH = 0x00;

    TRISBbits.TRISB7 = 0;   //set RB7 as an output

    ///////////////////////
    // Main Program Loop //
    ///////////////////////
    while(1)
    {
        PORTBbits.RB7 = 1;  //turn on the LED
        __delay_ms(500);    //wait 500ms
        PORTBbits.RB7 = 0;  //turn off the LED
        __delay_ms(500);    //wait 500ms
    }

    return 0;
}