[参考译文] TMS320F28377S：DSP F28377S、在去初始化之后 DMA 不工作

您好！  

我再次测试了该问题、使用"lab44_SPI_loopback _DMA"示例进行测试时、该问题正常。 但 在后面添加"DMAInitialize()"，然后 再次重复 lab44_SPI_loopback_DMA，发现 DMA 无法成功工作。

代码如下：

void main(void)
{
   Uint16 i;

// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the F2837xS_SysCtrl.c file.
   InitSysCtrl();

   //initial LSPCLK
   EALLOW;
   ClkCfgRegs.LOSPCP.bit.LSPCLKDIV = 0;        //000,LSPCLK = SYSCLK / 1
   EDIS;

// Step 2. Initialize GPIO:
// This example function is found in the F2837xS_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio();  // Skipped for this example
// Setup only the GP I/O only for SPI-A functionality
   InitSpiaGpio();

// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interrupts
   DINT;
   IER = 0x0000;
   IFR = 0x0000;

// Initialize PIE control registers to their default state:
// This function is found in the F2837xS_PieCtrl.c file.
   InitPieCtrl();

// 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 F2837xS_DefaultIsr.c.
// This function is found in F2837xS_PieVect.c.
   InitPieVectTable();

// 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 registers
   PieVectTable.DMA_CH5_INT= &local_D_INTCH5_ISR;
   PieVectTable.DMA_CH6_INT= &local_D_INTCH6_ISR;
   EDIS;   // This is needed to disable write to EALLOW protected registers

// Step 4. Initialize the Device Peripherals:
   dma_init();			// set up dma for SPI configuration
   spi_fifo_init();		// Initialize the SPI only

	// Ensure DMA is connected to Peripheral Frame 2 bridge (EALLOW protected)
	EALLOW;
	CpuSysRegs.SECMSEL.bit.PF2SEL = 1;
	EDIS;


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

	// Initialize the data buffers
	for(i=0; i<1024; i++)
	{
		sdata[i] = i;
		rdata[i]= 0;
		wTest[i] = 0;
	}
	rdata_point = 0;

// Enable interrupts required for this example
   PieCtrlRegs.PIECTRL.bit.ENPIE = 1;   // Enable the PIE block
   PieCtrlRegs.PIEIER7.bit.INTx5 = 1;	// Enable PIE Group 7, INT 1 (DMA CH1)
   PieCtrlRegs.PIEIER7.bit.INTx6 = 1;	// Enable PIE Group 7, INT 2 (DMA CH2)
   IER= M_INT7;							// Enable CPU INT6
   EINT;                                // Enable Global Interrupts

   StartDMACH6();		// Start SPI RX DMA channel
   StartDMACH5();		// Start SPI TX DMA channel

   done = 0;			// Test is not done yet

   while(!done);		// wait until the DMA transfer is complete

    {
        /************************************de initial DMA***********************************/
        while(wTest[1] < 10000)
        {
            wTest[1]++;
        }
        //added by xiaofei
        DMAInitialize();
        sInitSpiA();
        /************************************de initial DMA***********************************/


        // Step 4. Initialize the Device Peripherals:
        dma_init();          // set up dma for SPI configuration
        spi_fifo_init();     // Initialize the SPI only
        // Ensure DMA is connected to Peripheral Frame 2 bridge (EALLOW protected)
        EALLOW;
        CpuSysRegs.SECMSEL.bit.PF2SEL = 1;
        EDIS;

        // Initialize the data buffers
        for(i=0; i<1024; i++)
        {
            sdata[i] = i;
            rdata[i]= 0;
            wTest[i] = 0;
        }
        rdata_point = 0;

        // Enable interrupts required for this example
        PieCtrlRegs.PIECTRL.bit.ENPIE = 1;   // Enable the PIE block
        PieCtrlRegs.PIEIER7.bit.INTx5 = 1;   // Enable PIE Group 7, INT 1 (DMA CH1)
        PieCtrlRegs.PIEIER7.bit.INTx6 = 1;   // Enable PIE Group 7, INT 2 (DMA CH2)
        IER= M_INT7;                         // Enable CPU INT6
        EINT;                                // Enable Global Interrupts

        StartDMACH6();       // Start SPI RX DMA channel
        StartDMACH5();       // Start SPI TX DMA channel

        done = 0;            // Test is not done yet
        while(!done);       // wait until the DMA transfer is complete
    }


   while(done)
   {
       wTest[0]++;
   }
   // when the DMA transfer is complete the program will stop here
   ESTOP0;

}