N76E003 ---keil5 debug调试 卡在printf不运行了

keil5 debug调试 卡在printf不运行了，在逐步调试的时候到有printf函数就卡主动不了了。
代码如下，求指点一下！

```c
double  Bandgap_Value,Bandgap_Voltage;
    
void READ_BANDGAP()  
{ 
UINT8  BandgapHigh,BandgapLow; 
        set_IAPEN;        // Enable IAPEN 
        IAPAL = 0x0C; 
        IAPAH = 0x00; 
        IAPCN = 0x04; 
        set_IAPGO;            // Trig set IAPGO 
        BandgapHigh = IAPFD; 
        IAPAL = 0x0d; 
    IAPAH = 0x00; 
    IAPCN = 0x04; 
        set_IAPGO;            // Trig set IAPGO 
        BandgapLow = IAPFD; 
        BandgapLow = BandgapLow&0x0F; 
        clr_IAPEN;                 // Disable IAPEN   
        Bandgap_Value = (BandgapHigh<<4)+BandgapLow; 
        Bandgap_Voltage = 3072/(0x1000/Bandgap_Value); 
} 

double  Bandgap_Voltage,VDD_Voltage;
void ADC_Bypass (void)  // The first three times convert should be bypass 
 { 
  unsigned char ozc;
  for (ozc=0;ozc<0x03;ozc++)
  { 
            clr_ADCF;
            set_ADCS;
            while(ADCF == 0);
  }
}
void main (void)
{
        double bgvalue;
        ADCCON0&=0xF0;ADCCON0|=0x06;
        P03_Input_Mode;
    printf("hello the world");
        READ_BANDGAP();
        Enable_ADC_BandGap;
        Enable_ADC_AIN6;
            clr_ADCF;
            set_ADCS;
   while(ADCF == 0);
                bgvalue = (ADCRH<<4) + ADCRL;
                VDD_Voltage = (0Xfff/bgvalue)*Bandgap_Voltage;        
            printf ("\n Bandgap voltage = %e", Bandgap_Voltage);
            printf ("\n VDD voltage = %e", VDD_Voltage); 
        while(1);

```

你的printf重定向了吗