抽样定理.c

瑞泰ICETEK-F2812评估板资料

#include "DSP281x_Device.h"     // DSP281x Headerfile Include File
#include "DSP281x_Examples.h"   // DSP281x Examples Include File
#include "f2812a.h"
// Prototype statements for functions found within this file.
interrupt void adc_isr(void);

// Global variables used in this example:
Uint16 LoopCount;
Uint16 ConversionCount;
Uint16 Voltage1[1024];
Uint16 Voltage2[1024];
int i=0;

main() 
{
InitSysCtrl();//初始化cpu

   DINT;//关中断

   InitPieCtrl();//初始化pie寄存器
   

   IER = 0x0000;//禁止所有的中断
   IFR = 0x0000;


   InitPieVectTable();//初始化pie中断向量表
     
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.       
   EALLOW;  // This is needed to write to EALLOW protected register
   PieVectTable.ADCINT = &adc_isr;
   EDIS;    // This is needed to disable write to EALLOW protected registers
   AdcRegs.ADCTRL1.bit.RESET = 1;		// Reset the ADC module
	asm(" RPT #10 || NOP");				// Must wait 12-cycles (worst-case) for ADC reset to take effect
   AdcRegs.ADCTRL3.all = 0x00C8;		// first power-up ref and bandgap circuits
   
   AdcRegs.ADCTRL3.bit.ADCBGRFDN = 0x3;	// Power up bandgap/reference circuitry

   AdcRegs.ADCTRL3.bit.ADCPWDN = 1;		// Power up rest of ADC

// Enable ADCINT in PIE
   PieCtrlRegs.PIEIER1.bit.INTx6 = 1;
   IER |= M_INT1; // Enable CPU Interrupt 1
   EINT;          // Enable Global interrupt INTM
   ERTM;          // Enable Global realtime interrupt DBGM

   LoopCount = 0;
   ConversionCount = 0;
    
// Configure ADC
   AdcRegs.ADCMAXCONV.all = 0x0001;       // Setup 2 conv's on SEQ1
   AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0x0; // Setup ADCINA3 as 1st SEQ1 conv.
   AdcRegs.ADCCHSELSEQ1.bit.CONV01 = 0x1; // Setup ADCINA2 as 2nd SEQ1 conv.
   AdcRegs.ADCTRL2.bit.EVA_SOC_SEQ1 = 1;  // Enable EVASOC to start SEQ1
   AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1 = 1;  // Enable SEQ1 interrupt (every EOS)

// Configure EVA
// Assumes EVA Clock is already enabled in InitSysCtrl();
   EvaRegs.T1CMPR = 0x0080;               // Setup T1 compare value
   EvaRegs.T1PR = 0xb00;                 // Setup period register
   EvaRegs.GPTCONA.bit.T1TOADC = 1;       // Enable EVASOC in EVA
   EvaRegs.T1CON.all = 0x1042;            // Enable timer 1 compare (upcount mode)

// Wait for ADC interrupt
   while(1)
   {
      LoopCount++;
   }

}


interrupt void  adc_isr(void)
{

  Voltage1[ConversionCount] = AdcRegs.ADCRESULT0 >>4;
  Voltage2[ConversionCount] = AdcRegs.ADCRESULT1 >>4;

  // If 40 conversions have been logged, start over
  if(ConversionCount == 1023) 
  {
     ConversionCount = 0;
  }
  else ConversionCount++;

  // Reinitialize for next ADC sequence
  AdcRegs.ADCTRL2.bit.RST_SEQ1 = 1;         // Reset SEQ1
  AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1;       // Clear INT SEQ1 bit
  PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;   // Acknowledge interrupt to PIE
  if(i==0)
  { DA_DATA_L=0xff;                   //第一通道da数据输出量低8位
    DA_DATA_H=0x0f|DA_CHN1;    //第一通道da数据输出量高8位和通道号1
    DA_CTL=0;
    i=1;
  }
  else
  {
    DA_DATA_L=0x0;                   //第一通道da数据输出量低8位
    DA_DATA_H=0x0|DA_CHN1;    //第一通道da数据输出量高8位和通道号1
    DA_CTL=0;
    i=0;
  }
  return;
}