Pic Micro Simple Sleep mode Example

sleePic.c

/*
 * Author: Julio Alexander Aguilar Angulo ([email protected])
 * ISEN - Toulon: http://www.isen.fr/toulon/
 * myblog: alliselectronics.tumblr.com
 * compilateur:  XC8.   mcu:  12F1840.  Intosc:32KHz
 * Design notes:
 * In order to achieve the ULP features on cpu-circuit,
 * we will use the 32Khz LP internal oscillator to sleep-drive a system
 */
#include <xc.h>
//#include <stddef.h>
 #include <pic12lf1840.h>
 #pragma config CP=OFF, CPD=OFF, BOREN=OFF, WDTE=ON//
 #pragma config PWRTE=ON, FOSC=INTOSC, MCLRE=ON, IESO=OFF, CLKOUTEN=OFF
 #pragma config PLLEN=OFF, LVP=OFF, BORV=LO, WRT=OFF//ON

#define _XTAL_FREQ 31000//000 uncalibrated 31Khz
#define FOSC 31000//000 32Khz ulp
// macros to set the wdt engine
// -----------------------------------------------------------------
void main() {
    char counter;
// then, setup OPTION as a first thing to do after each reset
    OPTION_REG = 0b10001111;                // GPWU off, GPPU off,
                                            // RB0 falling edge int
                                            // TMR0 internal source (Fosc/4)
                                            // no TMR0 prescalling
                                            // optional 1:8 scale
    WPUA=0;   
    WDTCON =0b0011100;                       // wdt each 2sec, wdte on by code
// just to avoid an undesirable transient, let's reset ports first
    TRISA = 0b011101;
    OSCCON = 0b00000010 ;                   // Set the int-osc= 31khz -LP(uncal)
                                            // Ck src int-osc - no pll
    while(OSCSTATbits.LFIOFR==0){};         //wait untill LPOSC  is ready
// just to avoid an undesirable transient, let's reset ports here too
// As datasheet + users say, reload I/O setup again after reallocate ressources
    TRISA = 0b011101;
while(1) 
    {   
        CLRWDT();
        LATA =0b000000;
        __delay_ms(12000);
        LATA =0b00010;
        SLEEP();
    }
}