MCP3913 Analong Input

// DSPIC33FJ32MC202 Configuration Bit Settings

// 'C' source line config statements

#include <xc.h>
#define FCY 39000000UL 
#include <libpic30.h>



// FBS
#pragma config BWRP = WRPROTECT_OFF     // Boot Segment Write Protect (Boot Segment may be written)
#pragma config BSS = NO_FLASH           // Boot Segment Program Flash Code Protection (No Boot program Flash segment)

// FGS
#pragma config GWRP = OFF               // General Code Segment Write Protect (User program memory is not write-protected)
#pragma config GSS = OFF                // General Segment Code Protection (User program memory is not code-protected)

// FOSCSEL
#pragma config FNOSC = FRC           // Oscillator Mode (Primary Oscillator (XT, HS, EC) w/ PLL)
//#pragma config IESO = ON                // Internal External Switch Over Mode (Start-up device with FRC, then automatically switch to user-selected oscillator source when ready)

// FOSC
#pragma config POSCMD = XT              // Primary Oscillator Source (XT Oscillator Mode)
#pragma config OSCIOFNC = OFF           // OSC2 Pin Function (OSC2 pin has clock out function)
#pragma config IOL1WAY = ON             // Peripheral Pin Select Configuration (Allow Only One Re-configuration)
#pragma config FCKSM = CSECMD           // Clock Switching and Monitor (Clock switching is enabled, Fail-Safe Clock Monitor is disabled)

// FWDT
#pragma config WDTPOST = PS32768        // Watchdog Timer Postscaler (1:32,768)
#pragma config WDTPRE = PR128           // WDT Prescaler (1:128)
#pragma config WINDIS = OFF             // Watchdog Timer Window (Watchdog Timer in Non-Window mode)
#pragma config FWDTEN = OFF             // Watchdog Timer Enable (Watchdog timer enabled/disabled by user software)

// FPOR
#pragma config FPWRT = PWR128           // POR Timer Value (128ms)
#pragma config ALTI2C = OFF             // Alternate I2C  pins (I2C mapped to SDA1/SCL1 pins)
#pragma config LPOL = ON                // Motor Control PWM Low Side Polarity bit (PWM module low side output pins have active-high output polarity)
#pragma config HPOL = ON                // Motor Control PWM High Side Polarity bit (PWM module high side output pins have active-high output polarity)
#pragma config PWMPIN = ON              // Motor Control PWM Module Pin Mode bit (PWM module pins controlled by PORT register at device Reset)

// FICD
#pragma config ICS = PGD1               // Comm Channel Select (Communicate on PGC1/EMUC1 and PGD1/EMUD1)
#pragma config JTAGEN = OFF             // JTAG Port Enable (JTAG is Disabled)

void OpenUART1();
char BusyUART1();
char BusyUART1();
void PrintStringUART1();
void WriteCharToUART1(unsigned char Data);

int main(void) {
    // Configure PLL prescaler, PLL postscaler, PLL divisor
    PLLFBD=37; // M = 39
    CLKDIVbits.PLLPOST = 0; // N2 = 2
    CLKDIVbits.PLLPRE = 0; // N1 = 2

    // Initiate Clock Switch to Primary Oscillator with PLL (NOSC = 0b011)
    __builtin_write_OSCCONH(0x03);
    __builtin_write_OSCCONL(0x01);

    // Wait for Clock switch to occur
    while (OSCCONbits.COSC != 0b011);

    // Wait for PLL to lock
    while(OSCCONbits.LOCK != 1);    

    TRISBbits.TRISB15=0;
    TRISBbits.TRISB14=1;
    
     __builtin_write_OSCCONL(OSCCON & 0xDF);        // to clear IOLOCK
     // Assign U1TX to RP15, Pin 26
     RPOR7bits.RP15R = 3;
    // Assign U1RX to RP14, Pin 25
    RPINR18bits.U1RXR = 14;
    __builtin_write_OSCCONL(OSCCON | 0x40);        // to set IOLOCK
    
    unsigned char count=1;

    OpenUART1();

    while(1) {

       //Time from here
       WriteCharToUART1(count);
       WriteCharToUART1(count);
       //To here = 27us according to mplab stopwatch
    }
    return 0;
}

void OpenUART1(void) {
    U1MODEbits.STSEL=0;
    U1MODEbits.PDSEL=0;
    U1MODEbits.ABAUD=0;
    U1MODEbits.BRGH=1;
    U1BRG=12;
    
    U1MODEbits.UARTEN=1;
    U1STAbits.UTXEN=1;
    
}

char BusyUART1(void) {
    if (!IFS0bits.U1TXIF) {
        return 1;
    }else {
        IFS0bits.U1TXIF=0;
        return 0;
    }
}

void PrintStringUART1(unsigned char *String) {
    while(*String) {
        WriteCharToUART1(*String++);
    }
}

void WriteCharToUART1(unsigned char Data) {
    U1TXREG=Data;
    while(BusyUART1());
}