Application of AD inside STC series microcontroller

         The following example demonstrates the A/D conversion function of the STC89LE516AD/X2 series microcontroller. The clock is 11.0592MHz, and the conversion result is output to the serial port in hexadecimal format. The output result can be observed using the serial port debugger. (This code is taken from the Hongjing Technology chip manual and can run normally after being debugged by the author).

 #include

#include

//Define special function registers related to ADC

sfr P1_ADC_EN = 0x97; //A/D conversion function enable register

sfr ADC_CONTR = 0xC5; //A/D conversion control register

sfr ADC_DA TA = 0xC6; //A/D conversion result register

typedef unsigned char INT8U;

typedef unsigned int INT16U;

void delay(INT8U delay_time) // delay function

{

         INT8U n;

         INT16U m;

         for (n=0;n

                  {

                            for(m=0;m<10000;m++);

                  }

}

INT8U get_AD_result(INT8U channel)

{

         INT8U AD_finished = 0; //Store A/D conversion flag

         ADC_DA TA = 0;

         ADC_CONTR = channel; // Select A/D current channel

         delay(1); //Make the input voltage stable

         ADC_CONTR |= 0x08; //0000,1000 Set ADC_START = 1 to start A/D conversion

         AD_finished = 0;

         while ( AD_finished == 0 ) // Wait for A/D conversion to finish

         {

                  AD_finished = (ADC_CONTR & 0x10); //0001,0000, ADC_FLAG ==1 Test A/D conversion completion

         }

         ADC_CONTR &= 0xF7; //1111,0111 set ADC_START = 0, turn off A/D conversion,

         return (ADC_DA TA); // Return A/D conversion result

}

void main()

{

         P1 = P1 | 0x63; // 0110,0011, to set the P1.x port for A/D conversion, first set it to high

         P1_ADC_EN = 0x63; //0110,0011, P1.0, P1.1, P1.5, P1.6 of P1 are set as A/D conversion input pins

         // Disconnect the internal pull-up resistors of P1.0 and P1.1

                  get_AD_result(0); //P1.0 is the current channel of A/D

                  get_AD_result(1); //P1.1 is the current channel of A/D