STM8 ADC problem on STM8S003K3

void SetupADC()
  {
   // ADC1_TRDL=1; 
//ADC_CR1_ADON = 1;       //  Turn ADC on, note a second set is required to start the conversion.
ADC_CSR_CH = 0x00;      //  ADC on AIN4 only.
ADC_CR3_DBUF = 0;
ADC_CR2_ALIGN = 1;      //  Data is right aligned.
//ADC_CSR_EOCIE = 1;      //  Enable the interrupt after conversion completed.
ADC_CR1_CONT= 0;
ADC_CSR_AWD = 0;

}

void get_adc()
{
  unsigned char low, high;
  ADC_CR1_ADON = 1;       //  Turn ADC on, note a second set is required to start the conversion.
  ADC_CR1_ADON = 1;       //  Turn ADC on, note a second set is required to start the conversion.
  value1=0;
 
  while(ADC_CSR_EOC== 0); // Wait till EOC
  low = ADC_DRL;            //    Extract the ADC reading.
high = ADC_DRH;
     value1 = (high*256)+low;
     
      
}