int ledvalue=0xaa;
void main( void )
{ WDTCTL = WDTPW + WDTHOLD; //关闭看门狗 P11DIR = BIT1+BIT2; // P11.1-2 to output direction P11SEL |= BIT1+BIT2; // P11.1-2 to output SMCLK,MCLK P5SEL |= 0x0C; // Port select XT2
UCSCTL6 &= ~XT2OFF; // Enable XT2 UCSCTL3 |= SELREF_2; // FLLref = REFO // Since LFXT1 is not used, // sourcing FLL with LFXT1 can cause // XT1OFFG flag to set UCSCTL4 |= SELA_2; // ACLK=REFO,SMCLK=DCO,MCLK=DCO
// Loop until XT1,XT2 & DCO stabilizes do { UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + XT1HFOFFG + DCOFFG); // Clear XT2,XT1,DCO fault flags SFRIFG1 &= ~OFIFG; // Clear fault flags }while (SFRIFG1&OFIFG); // Test oscillator fault flag
UCSCTL6 &= ~XT2DRIVE0; // Decrease XT2 Drive according to // expected frequency UCSCTL4 |= SELS_5 + SELM_5; // SMCLK=MCLK=XT2