做一个简单的28335ADC采样但是采样值一直不正确

只看该作者 · 2016-11-27 20:39

只做一个简单的ADC采样，但是才扬州一直不正确，无论输入什么，是接地还是悬空还是接到一个直流电压的正极，ADCRESULT显示一直是FXXX到EXXX跳动，到底是为什么呢 ADCLO也接地试过输出并没有变化

只看该作者 · 2016-11-27 20:44

#include "DSP2833x_Device.h"    // DSP2833x Headerfile Include File
#include "DSP2833x_Examples.h" // DSP2833x Examples Include File

interrupt void adc_isr(void);

Uint16 LoopCount;
Uint16 ConversionCount;
Uint16 Voltage1[10];

main()
{

InitSysCtrl();

EALLOW;
#if (CPU_FRQ_150MHZ)    // Default - 150 MHz SYSCLKOUT
   #define ADC_MODCLK 0x3 // HSPCLK = SYSCLKOUT/2*ADC_MODCLK2 = 150/(2*3) = 25.0 MHz
#endif
#if (CPU_FRQ_100MHZ)
   #define ADC_MODCLK 0x2 // HSPCLK = SYSCLKOUT/2*ADC_MODCLK2 = 100/(2*2) = 25.0 MHz
#endif
EDIS;

DINT;

InitPieCtrl();

// Disable CPU interrupts and clear all CPU interrupt flags:
IER = 0x0000;
IFR = 0x0000;

InitPieVectTable();

EALLOW;
PieVectTable.ADCINT = &adc_isr;
EDIS;

InitAdc();  // For this example, init the ADC

// Step 5. User specific code, enable interrupts:

// 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;

AdcRegs.ADCMAXCONV.all = 0x0000;    // Setup 1 conv's on SEQ1
AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0x7; // Setup ADCINA0 as 1st SEQ1 conv.
AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1 = 1;// Enable SOCA from ePWM to start SEQ1
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1 = 1;  // Enable SEQ1 interrupt (every EOS)

   EPwm1Regs.ETSEL.bit.SOCAEN = 1;       // Enable SOC on A group  ADC转换序列A启动使能位 1使能
EPwm1Regs.ETSEL.bit.SOCASEL = 4;    // Select SOC from from CPMA on upcount  EPWMxSOCA脉冲生成选择位
                                                   //100:计数器增加时，TBCTR=CMPA
EPwm1Regs.ETPS.bit.SOCAPRD = 1;       // Generate pulse on 1st event  该位决定发生多少个事件后产生EPWMxSOCA


EPwm1Regs.TBPRD = 0xFFFF;             // Set period for ePWM1 确定定时器的周期，设置PWM的频率
                                          //2^16=65536
                                          //PWM的周期也就是采样周期为[1/(75*1000000)]*65536
EPwm1Regs.TBCTR=0X0000;                //清除TB计数器

EPwm1Regs.TBCTL.bit.CTRMODE = 0;    // count up and start定时器计数模式  00：连续增模式

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

}

interrupt void  adc_isr(void)
{

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

  // If 40 conversions have been logged, start over
  if(ConversionCount == 9)
  {
   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

  return;
}