// PIC10F322 Configuration Bit Settings
// 'C' source line config statements
// CONFIG
#pragma config FOSC = INTOSC    // Oscillator Selection bits (INTOSC oscillator: CLKIN function disabled)
#pragma config BOREN = OFF      // Brown-out Reset Enable (Brown-out Reset disabled)
#pragma config WDTE = ON        // Watchdog Timer Enable (WDT enabled)
#pragma config PWRTE = OFF      // Power-up Timer Enable bit (PWRT disabled)
#pragma config MCLRE = OFF      // MCLR Pin Function Select bit (MCLR pin function is digital input, MCLR internally tied to VDD)
#pragma config CP = OFF         // Code Protection bit (Program memory code protection is disabled)
#pragma config LVP = OFF        // Low-Voltage Programming Enable (High-voltage on MCLR/VPP must be used for programming)
#pragma config LPBOR = OFF      // Brown-out Reset Selection bits (BOR disabled)
#pragma config BORV = LO        // Brown-out Reset Voltage Selection (Brown-out Reset Voltage (Vbor), low trip point selected.)
#pragma config WRT = OFF        // Flash Memory Self-Write Protection (Write protection off)

#include <xc.h>
#include <pic10f322.h>

#define _XTAL_FREQ 4000000

enum p_state{OFF, ON}state;
unsigned char check=1;

void init_PWM();
void enter_sleep();
void init_osc();
void init();
void sleep_128ms();

void main(void) {
    //Setup prescalar for WDT
    //WDTPSx_bit used, default 2 seconds seems ok
    //WDTPS0=0;WDTPS1=1;WDTPS2=0;WDTPS3=1;WDTPS4=0;//1 s
    WDTPS0=1;WDTPS1=0;WDTPS2=0;WDTPS3=1;WDTPS4=0;//0.5 s
    //WDTPS0=0;WDTPS1=0;WDTPS2=0;WDTPS3=1;WDTPS4=0;//0.25 s

    //turn off voltage reference
    //FVREN = 0; //Default is off so no need to do manually
    VREGPM1 = 1; //Internal power regulator in power save

    //setup pins (inputs/outputs)
    ANSELA = 0x00; //all digital 
    PIE1bits.NCO1IE = 0; //RA2 as output
    CLKRCONbits.CLKROE = 0; //RA2 as output
    TRISA = 0x08; //RA3 input, rest output
    PORTA = 0x00;

    //Go to sleep, might accidently wake once
    enter_sleep();
    enter_sleep();

    unsigned char state_cnt=0;
    
    while(1){
        CLRWDT();
        
        //increase state_cnt if magnet is near Hall sensor
        if(state_cnt>1 && PORTAbits.RA3){
            state_cnt=0;
            if(!check)check=1;
            else
            {
                enter_sleep();
            }
        }
        
        if(0==PORTAbits.RA3){
            ++state_cnt;
        }
        
        PWM1DCH = 0xFF;
        PWM1DCL = 0xFF;
        PWM2DCH = 0xFF;
        PWM2DCL = 0xFF;

        while (!INTCONbits.TMR0IF);
        INTCONbits.TMR0IF = 0;
    }
}

void init(){
    init_osc();
    //setup timer for setting how fast effects change
    //Last three bits control PS
    //000 is 1:2
    //001 is 1:4
    //and so on...
    //111 is 1:256
    //Changing from 110 to 101 makes all effects
    //update twice as fast.
    OPTION_REG = 0b00000110; 
    INTCONbits.TMR0IF = 0;
    init_PWM(); 
}

void enter_sleep(){
    state=OFF;

    //Turn off PWM
    PWM1CONbits.PWM1OE = 0;
    PWM2CON0bits.PWM2OE = 0;
    
    //Turn off Hall
    PORTAbits.RA2 = 0; 
    
    //enter sleep, resume on WDT
    IRCF0 = 0; IRCF1 = 0; IRCF2 = 0;
    SLEEP();
    while(OFF==state){
        if(!STATUSbits.nTO){
            //woke due to WDT
            //Check if hall switch is pulled low, if, then wake (must first enable hall sensor)
            PORTAbits.RA2 = 1;  
            sleep_128ms();
            if(0 == PORTAbits.RA3){
                state = ON;
            }
            else{
                PORTAbits.RA2=0;    
                SLEEP();
            }
        }
    }
    check=0;
    PORTAbits.RA2 = 1; //Turn hall sensor on
    //Turn pwm on
    PWM1CONbits.PWM1OE = 1;
    PWM2CON0bits.PWM2OE = 1;
    //sleep to make sure it is on before leaving sleep
    sleep_128ms();
    init();
}

void sleep_128ms(){
    WDTPS0=1;WDTPS1=1;WDTPS2=1;WDTPS3=0;WDTPS4=0;
    SLEEP();
    NOP();
    WDTPS0=1;WDTPS1=0;WDTPS2=0;WDTPS3=1;WDTPS4=0; //set back WDT    
}

void init_PWM() {
    //set up for pwm
    TRISA0 = 1;
    TRISA1 = 1;
    PWM1CON = 0x00;
    PWM2CON = 0x00;
    PWM1DCH = 0x00;
    PWM1DCL = 0x00;
    PWM2DCH = 0x00;
    PWM2DCL = 0x00;
    ////set up Timer2
    PIR1bits.TMR2IF = 0;
    T2CON = 0b00000100; //timer on, no post scalar, prescaler is 1
    //enable pwm
    PWM1CONbits.PWM1EN = 1;
    PWM2CON0bits.PWM2EN = 1;
    while (!PIR1bits.TMR2IF); //wait for overflow
    TRISA0 = 0;
    TRISA1 = 0;
    PWM1CONbits.PWM1OE = 1;
    PWM2CON0bits.PWM2OE = 1;
    return;
}

void init_osc(){
    #if (4000000 == _XTAL_FREQ) 
        IRCF0 = 1;
        IRCF1 = 0;
        IRCF2 = 1; //4MHz, 0 0 0 is 31kHz low freq oscillator
    #endif
    #if (8000000 == _XTAL_FREQ) 
        IRCF0 = 0;
        IRCF1 = 1;
        IRCF2 = 1;
    #endif
}