[参考译文] TMS320F28379D：F28379

您好！

请参阅我们的 ADC 输入电路设计应用手册： https://www.ti.com/lit/spract6

我不认为该应用手册中包含的内容会导致您出现错误、因为这通常会导致您的输出低于预期。

您是否确定已正确设置图形？ 如果你将 ADC 结果存储在一个缓冲器中、你是否看到大多数样本接近4096？  

您是否使用了我们的示例？ 如果是、哪一个？

此致、

Ben Collier

您好！

是的、我正在使用缓冲器、正如您所说的、大多数样本4095。 图形应该没问题。 代码附在下面。 我使用 TI 示例作为缓冲器、左侧是我的工作。  

//###########################################################################
// Author: Halit Durukan
//###########################################################################
#include "F28x_Project.h"     // Device Headerfile and Examples Include File


#define ADC_BUF_LEN 1000

//###########################################################################
// Global variables used in the project before main function. Declare other     // variables in this section of the code.
//###########################################################################
Uint16 Result = 0;
Uint16 AdcBuf[ADC_BUF_LEN];
//###########################################################################
// Declare the service routines and functions
//###########################################################################


interrupt void xint1_isr(void);
interrupt void cpu_timer(void);
interrupt void adcint1_isr(void);

//######################   Beginning of the main code #######################


void main(void)
{

// Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the F2837xD_SysCtrl.c file.
    InitSysCtrl();


// Clear all interrupts and initialize PIE vector table:
// Disable CPU interrupts
    DINT;

// Initialize the PIE control registers to their default state.
// The default state is all PIE interrupts disabled and flags
// are cleared.
// This function is found in the F2837xD_PieCtrl.c file.
    InitPieCtrl();

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

// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example.  This is useful for debug purposes.
// The shell ISR routines are found in F2837xD_DefaultIsr.c.
// This function is found in F2837xD_PieVect.c.
    InitPieVectTable();


// Enable global Interrupts and higher priority real-time debug events:
    //EINT;  // Enable Global interrupt INTM
    //ERTM;  // Enable Global realtime interrupt DBGM


//###########################################################################
// User specific code: Your code comes here.
//###########################################################################
    EALLOW;

    AdcaRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4
    AdcaRegs.ADCCTL1.bit.ADCPWDNZ = 1; //power up the ADC
    AdcaRegs.ADCCTL1.bit.INTPULSEPOS = 1; //Set interrupt pulse positions to late
    AdcaRegs.ADCCTL2.bit.RESOLUTION = 0; // 12-bit resolution
    AdcaRegs.ADCCTL2.bit.SIGNALMODE = 0; // Single-ended (12-bit mode only)
    DELAY_US(1000); //have to delay at least 500 microseconds before using ADC

    AdcaRegs.ADCSOC0CTL.bit.CHSEL = 0; //SOC0 will convert pin ADCINA0
    AdcaRegs.ADCSOC0CTL.bit.ACQPS = 39; //0.2 micro seconds for sampling window (40 x 5ns = 0.2 micro secs)
    AdcaRegs.ADCSOC0CTL.bit.TRIGSEL = 0x01; //trigger on CPU Timer 0

    CpuTimer0Regs.PRD.all = 10000 - 1;//Load period value. 20 kHz sampling (50 micro seconds period)
    CpuTimer0Regs.TPR.bit.TDDR = 0;//Set the prescale value for the timer as 1.
    CpuTimer0Regs.TCR.bit.TSS = 1;//Stop the timer.
    CpuTimer0Regs.TCR.bit.TRB = 1;//Reload the timer.
    CpuTimer0Regs.TCR.bit.TIE = 1;//Enable the Timer0 interrupt in the peripheral level.
    CpuTimer0Regs.TCR.bit.TSS = 0;//Start the timer.

    AdcaRegs.ADCINTSEL1N2.bit.INT1SEL = 0; //EOC0 will set INT1 flag
    AdcaRegs.ADCINTSEL1N2.bit.INT1CONT = 1; //interrupts will be generated
     //whether the ADCINTFLG is
     //cleared or not
    AdcaRegs.ADCINTSEL1N2.bit.INT1E = 1; //enable INT1 flag

//Redirect the address of the ISR:
    PieVectTable.ADCA1_INT = &adcint1_isr;

    PieCtrlRegs.PIECTRL.bit.ENPIE = 1; // Enable the PIE block
    PieCtrlRegs.PIEIER1.bit.INTx1 = 1; // Enable PIE Group 1 INT1 ADCA1

    IER |= M_INT1;//Enable CPU INT1 includes Xint1
    EINT;//Enable global interrupt mask INTM.
    ERTM;
    EDIS;


    for (;;)
    {

    }
}

//######################   End of main code #######################


//#################### Interrupt Service Routines #################

interrupt void adcint1_isr(void)
{
    static Uint16 *AdcBufPtr = AdcBuf;
    *AdcBufPtr++ = AdcaResultRegs.ADCRESULT0;
    // Brute Force the circular buffer
    if (AdcBufPtr == (AdcBuf + ADC_BUF_LEN))
    {
        AdcBufPtr = AdcBuf;
    }
    //Result = AdcaResultRegs.ADCRESULT0;
    GpioDataRegs.GPBTOGGLE.bit.GPIO32 = 1;
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}