CCS: MSP430F6638

// (c)2010 by Texas Instruments Incorporated, All Rights Reserved.
/*----------------------------------------------------------------------------+
|                                                                             |
|                              Texas Instruments                              |
|                                                                             |
|                          MSP430 USB-Example (CDC/HID Driver)                |
|                                                                             |
+-----------------------------------------------------------------------------*/
/*  Source: main.c, v2.0 2009/08/03       
-------------------------------------------------------------------------------+
Local Echo Demo:

 This USB demo example is to be used with a PC application (e.g. HyperTerminal)
 The demo application demonstartes a local echo; Characters that are 
 transmitted from PC are echoed back.

 NOTE: In order to see the local echo in Hyper Terminal goto File -> Propoerties 
 -> Settings -> ASCII Setup and check the "Echo Typed Characters Locally"

------------------------------------------------------------------------------+
 Please refer to the MSP430 USB API Stack Programmer's Guide,located 
 in the root directory of this installation for more details.
------------------------------------------------------------------------------*/




#include<msp430f6638.h>
#include <math.h>
#include <string.h>
#include <intrinsics.h>



/*----------------------------------------------------------------------------+
| Main Routine                                                                |
+----------------------------------------------------------------------------*/
#define st(x)      do { x } while (__LINE__ == -1)
#define SELECT_MCLK_SMCLK(sources) st(UCSCTL4 = (UCSCTL4 & ~(SELM_7 + SELS_7)) | (sources);)
#define USB_MCLK_FREQ 4000000                // MCLK frequency of MCU, in Hz
void Port_init(void);
void FLL_config(unsigned int fsystem, unsigned int ratio);

void main(void)
{
        WDTCTL = WDTPW + WDTHOLD; // Stop WDT

        __disable_interrupt(); // Disable global interrupts
        Port_init();

        while(BAKCTL & LOCKBAK) // Unlock XT1 pins for operation
            BAKCTL &= ~(LOCKBAK);

		 // Setup Clock
		UCSCTL6 &= ~(XT1OFF);                  // XT1 On
		UCSCTL6 |= XCAP_3;                        // Internal load cap

		do
		{
					UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + DCOFFG);   // Clear XT2,XT1,DCO fault flags
					SFRIFG1 &= ~OFIFG;                                                        // Clear fault flags
		}while (SFRIFG1&OFIFG);                                                             // Test oscillator fault flag

		// Start the FLL, which will drive MCLK (not the crystal)
		FLL_config(USB_MCLK_FREQ/1000, USB_MCLK_FREQ/32768);                  // set FLL (DCOCLK)

		__enable_interrupt();                                              // enable global interrupts
		RTCCTL01 |= RTCRDYIE + RTCHOLD;             // BCD mode, RTC hold, enable RTC read ready interrupt
		RTCSEC=0;
		RTCMIN=0;
		RTCHOUR=10;
		RTCDAY=12;
		RTCMON=6;
		RTCYEAR=19;
		RTCCTL01 &= ~(RTCHOLD);

		TA0CTL = TASSEL_1 +ID_3+ MC_1+TACLR;
		TA0CCR0 =9;
		TA0CCTL0 = CCIE;

		while(1)
		{
			  __bis_SR_register(LPM3_bits);
			  __no_operation();
			  __no_operation();
		}
}

void FLL_config(unsigned int fsystem, unsigned int ratio)
{
	unsigned int d, dco_div_bits;
	unsigned int mode = 0;


	unsigned int srRegisterState = __get_SR_register() & SCG0;
	__bic_SR_register(SCG0);

	d = ratio;
	dco_div_bits = FLLD__2; // Have at least a divider of 2

	if (fsystem > 16000) {
	d >>= 1 ;
	mode = 1;
	}
	else {
	fsystem <<= 1; // fsystem = fsystem * 2
	}

	while (d > 512) {
		dco_div_bits = dco_div_bits + FLLD0; // Set next higher div level
		d >>= 1;
	}

	UCSCTL0 = 0x0000; // Set DCO to lowest Tap
	UCSCTL2 &= ~(0x03FF); // Reset FN bits
	UCSCTL2 = dco_div_bits | (d - 1);

	if (fsystem <= 630) // fsystem < 0.63MHz
	UCSCTL1 = DCORSEL_0;
	else if (fsystem < 1250) // 0.63MHz < fsystem < 1.25MHz
	UCSCTL1 = DCORSEL_1;
	else if (fsystem < 2500) // 1.25MHz < fsystem < 2.5MHz
	UCSCTL1 = DCORSEL_2;
	else if (fsystem < 5000) // 2.5MHz < fsystem < 5MHz
	UCSCTL1 = DCORSEL_3;
	else if (fsystem < 10000) // 5MHz < fsystem < 10MHz
	UCSCTL1 = DCORSEL_4;
	else if (fsystem < 20000) // 10MHz < fsystem < 20MHz
	UCSCTL1 = DCORSEL_5;
	else if (fsystem < 40000) // 20MHz < fsystem < 40MHz
	UCSCTL1 = DCORSEL_6;
	else
	UCSCTL1 = DCORSEL_7;

	while (SFRIFG1 & OFIFG) { // Check OFIFG fault flag
			  UCSCTL7 &= ~(DCOFFG+XT1LFOFFG+XT1HFOFFG+XT2OFFG); // Clear OSC flaut Flags
			  SFRIFG1 &= ~OFIFG; // Clear OFIFG fault flag
	}

	if (mode == 1) { // fsystem > 16000
			SELECT_MCLK_SMCLK(SELM__DCOCLK + SELS__DCOCLK); // Select DCOCLK
	}
	else {
		   SELECT_MCLK_SMCLK(SELM__DCOCLKDIV + SELS__DCOCLKDIV); // Select DCODIVCLK
	}

		   __bis_SR_register(srRegisterState); // Restore previous SCG0

}

void Port_init(void){

	P1SEL=0X00;
	P2SEL=0X00;
	P3SEL=0X00;
	P4SEL=0X00;
	P5SEL=0X00;
	P6SEL=0X00;
	P7SEL=0X00;
	P8SEL=0X00;
	P9SEL=0X00;

	P1DIR= 0XFF;
	P2DIR= 0XFF;
	P3DIR= 0XFF;
	P4DIR= 0XFF;
	P5DIR= 0XFF;
	P6DIR= 0XFF;
	P7DIR= 0XFF;
	P8DIR= 0XFF;
	P9DIR= 0XFF;

	P1OUT=0X3f;
	P2OUT=0X00;
	P3OUT=0X00;
	P4OUT=0X00;
	P5OUT=0X00;
	P6OUT=0X00;
	P7OUT=0X00;
	P8OUT=0X00;
	P9OUT=0X3f;

}


#pragma vector=RTC_VECTOR
__interrupt void RTC_ISR(void)
{
     while(BAKCTL & LOCKBAK)
       BAKCTL &= ~(LOCKBAK);

  switch(__even_in_range(RTCIV,14))
  {
   case  0: break;                           // Vector  0:  No interrupt
   case  2:

	   // Vector  2:  RTCRDYIFG (RTC ready)
	   RTCCTL01 &= ~(RTCRDYIFG);
	   break;
   case  4: break;                           // Vector  4:  RTCEVIFG // RTC interval timer
   case  6: break;                           // Vector  6:  RTCAIFG// alarm
   case  8: break;                           // Vector  8:  RT0PSIFG //prescalar0
   case 10: break;                           // Vector 10:  RT1PSIFG // prescale 1
   case 12: break;                         // Vector 12:  RTCOFIFG
   case 14: break;                           // Vector 14:  Reserved
   default: break;
  }
}

// Timer0 A0 interrupt service routine
#pragma vector=TIMER0_A0_VECTOR
 __interrupt void TIMER0_A0_ISR(void)
{
	 //timer value = 2.44140625 msec
}