gradually increasing PWM

Hi,

       Here is the code of pwm generation, but i want gradual increase in pwm and it should get out on LED connected to port 3.7, In code i have used external oscillator of 32KHz , what modifications should i do for that???? please help me :((

#include<msp430x21x2.h>

#include

volatileunsigned int i;

void

BCSCTL3 |= LFXT1S0;

// + LFXT1OF; // LFXT1S1 = 3-16Mhz BCSCTL1|=DIVA_3;

BCSCTL3|=XCAP_2;

do

{IFG1 &= ~OFIFG;

// Clear OSCFault flag

// Time for flag to set

}

// OSCFault flag still set?

BCSCTL2 |= SELM_3;

// MCLK = LFXT1 (safe)

P1DIR|=0X10;

P2DIR|=0X02;

P3DIR|=0X80;

 P1SEL|= 0X10;

P2SEL|= 0X02;

P3SEL|= 0X80;

TA1CCR0 = pwmpr;

// + CCIE; //TA1CCR1=start1; // + CM_2 + SCCI + SCS;

TA1CTL = TASSEL_1 + MC_1 + TAIE;

// + TACLR;+ TAIFG; + ID_3 ; ACLK, up

__bis_SR_register(GIE);

//_EINT(); CPU off

}

//**************************************************************

void TIMER1_A1(void)

{

unsigned int j=50000;

if (TA1IV==0X0a)

TA1CCR1+=10;

{

do

j--;}

while (j!=0);

}

}