/*
 * PWM registers configuration
 * Fosc = 8000000 Hz
 * Fpwm = 37735.85 Hz (Requested : 38000 Hz)
 * Duty Cycle = 50 %
 * Resolution is 7 bits
 * Prescaler is 1
 * Ensure that your PWM pin is configured as digital output
 * see more details on http://www.micro-examples.com/
 * this source code is provided 'as is',
 * use it at your own risks
 */
PR2 = 0b00110100 ;
T2CON = 0b00000100 ;
CCPR1L = 0b00011010 ;
CCP1CON = 0b00011100 ;

    // speed up the clock to 8MHz
    OSCCONbits.IRCF0=1; OSCCONbits.IRCF1=1;
    OSCCONbits.IRCF1=1;
    OSCCONbits.IRCF2=1;
    OSCCONbits.SCS0=0;
    OSCCONbits.SCS1=0;
    //18F1330 Speed clock up to 32MHz using PLL
    OSCTUNEbits.PLLEN=1;
    ADCON1 = 0; // make RA0 digital
    TRISA = 0xFE;
    while(1)
        {
        PORTA = 0xFF;
        delay_us(13);
        PORTA = 0x00;    
        delay_us(13);
    }

#include <system.h>

//Target PIC18F1320 configuration word

//#pragma DATA _CONFIG, _CP_OFF & _LVP_OFF & _BODEN_OFF & _MCLRE_ON & _PWRTE_ON & _WDT_OFF & _INTOSC_OSC_NOCLKOUT

#pragma DATA  _CONFIG1H, _INTIO2_OSC_1H & _FSCM_OFF_1H
#pragma DATA  _CONFIG2L, _PWRT_ON_2L & _BOR_OFF_2L & _BORV_27_2L
#pragma DATA  _CONFIG2H, _WDT_OFF_2H & _WDTPS_32K_2H
#pragma DATA  _CONFIG3H, _MCLRE_ON_3H
#pragma DATA  _CONFIG4L, _DEBUG_OFF_4L & _LVP_OFF_4L & _STVR_ON_4L

#pragma DATA  _CONFIG5L, _CP0_OFF_5L & _CP1_OFF_5L
#pragma DATA  _CONFIG5H, _CPB_OFF_5H & _CPD_OFF_5H
#pragma DATA  _CONFIG6L, _WRT0_OFF_6L & _WRT1_OFF_6L
#pragma DATA  _CONFIG6H, _WRTC_OFF_6H & _WRTB_OFF_6H & _WRTD_OFF_6H
#pragma DATA  _CONFIG7L, _EBTR0_OFF_7L & _EBTR1_OFF_7L
#pragma DATA  _CONFIG7H, _EBTRB_OFF_7H

//Set clock frequency
#pragma CLOCK_FREQ    8000000


// 38 khz

#define CCP1Period    12
#define    CCP1DutyCy    25



bit        running = 0;

unsigned char    turnon[6] = { 0x40, 4, 1, 0, 0xbc, 0xbd};

void interrupt( void )
{
    // Handle timer1 interrupt
    // Used to time the length of pulses
    if( pir1.TMR1IF )
    {
        running = 0;
        t1con.TMR1ON = 0;    // Turn TIMER1 off
        pir1.TMR1IF = 0; //clear timer 1 interrupt bit
    }
}

void xmit_pulse(short micro_pulse)
{
    static short    clock_count;
    clock_count = 65536 - micro_pulse;
    LOBYTE( tmr1l, clock_count);
    HIBYTE( tmr1h, clock_count);
    pir1.TMR1IF = 0;        // Reset overflow bit
    t1con.TMR1ON = 1;    // Turn TIMER1 on
    running = 1;

    trisb.3 = 0;
    t2con.TMR2ON = 1;
    while (running) ;        // Wait for pulse time to end    
    t2con.TMR2ON = 0;
    tmr2 = 0;
    portb.3 = 0;
    trisb.3 = 1;
}

void send_on(void) {
    static char    i;
    static char    j;
    static char    t;
    static unsigned char    *ovalue;
    static unsigned char    k;

//    Send it 3 times
    for (k = 0; k < 3; k++) {
        ovalue = &turnon;
        xmit_pulse(3550);    // 4 ms header
        delay_100us(10);    // 1 ms
        delay_10us(6);        // .6 ms
        for (i = 0; i < 6; i++) {
            for (j = 8; j > 0; j--) {
                t = j - 1;
                if (test_bit(*ovalue, t)) {
//                    A one
                    xmit_pulse(512);        // 400 micro s 
                    delay_100us(10);        // 1 ms
                    delay_10us(2);            // .2 ms
                }
                else {
//                    A zero
                    xmit_pulse(512);        // 400 micro s
                    delay_100us(3);            // 400 micro s
                }
            }
            ovalue++;
        }
//        End bit
        xmit_pulse(400);
        delay_ms(70);
    }
}
void main( void )
{
    static unsigned char    Low;
    static unsigned char    High;
    static unsigned int        Duty = CCP1DutyCy;
    // Set speed to 8 mhz
    set_bit(osccon, IRCF2);
    set_bit(osccon, IRCF1);
    set_bit(osccon, IRCF0);
    ccp1con = 0;        // CCP Module off
    tmr2 = 0;            // Clear Timer 2
    //Configure port B
    trisb = 0x00;
    trisb.3 = 1;
    intcon2.NOT_RBPU = 0;
    //Initialize port B
    portb = 0;

    //Set timer 1
    //prescaler rate 1:1
    //Internal clock (FOSC/4)
    t1con = 00001000b;

    // Configure Capture/Compare/PWM for PWM
    // at 38khz.  
    //Set timer 2 prescaler rate
    // T2CPS = 1:4
    t2con = 00000001b;
    //t2con = 0;
    pr2 = CCP1Period;
    Low = Duty & 3;
    High = Duty >> 2;
    ccpr1l = High;
    ccp1con = 00001100b;
    ccp1con.5 = Low.1;
    ccp1con.4 = Low.0;

    intcon.PEIE = 1;        // Enable peripheral interrupts
    intcon.GIE = 1;         // Enable global interrupt
    pie1.TMR1IE = 1;        // Enable Timer 1 interrupts

// test    
    trisb.3 = 0;
    t2con.TMR2ON = 1;
    while (1) ;
//  test

//    Main Loop
    send_on();
    while (1) {
    }
}

// 38 khz

#define CCP1Period    12
#define    CCP1DutyCy    25

    static unsigned char    Low;
    static unsigned char    High;
    static unsigned int        Duty = CCP1DutyCy;

    // Configure Capture/Compare/PWM for PWM
    // at 38khz.  
    //Set timer 2 prescaler rate
    // T2CPS = 1:4
    t2con = 00000001b;
    //t2con = 0;
    pr2 = CCP1Period;
    Low = Duty & 3;
    High = Duty >> 2;
    ccpr1l = High;
    ccp1con = 00001100b;
    ccp1con.5 = Low.1;
    ccp1con.4 = Low.0;

    trisb.3 = 0;
    t2con.TMR2ON = 1;

// 37.7kHZ PWM IR carrier signal
#include <p18f1320.h>
#pragma config WDT = OFF,OSC = INTIO2,LVP = OFF
void main(void) {    
    OSCCON=0x72; // speed up the clock to 8MHz
    ADCON1 = 0; 
    TRISBbits.TRISB3 = 0;
    PR2 = 0b00110100 ;
    T2CON = 0b00000100 ;
    CCPR1L = 0b00011010 ;
    CCP1CON = 0b00011100 ;
    while(1) {
     }    
}