[参考译文] TMS320F28388D：如何使用 DMA 和 eCAP

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/1221481/tms320f28388d-how-to-use-dma-and-ecap

尊敬的专家：

请告诉我如何为 F2838x 使用 DMA 和 eCAP。

问题1：您能否在以下代码中指出任何缺失的设置或错误？

我们已根据 C2000ware 中的以下示例代码进行检查、但我们无法将 eCAP2Reg 的 CAP1、CAP2、CAP3和 CAP4数据传输至内部 RAM。  从0x00开始、传输目的的内容没有改变。

我更改了"dma_ex1_gsram_transfer"的默认内容的以下内容。 路径：C：\ti\c2000\C2000Ware_4_02_00_00\driverlib\f2838x\examples\C28x\dma
srcAddr =(const void *)(ECAP2_BASE + 4)；
DMA_configBurst (DMA_CH6_BASE、burst、0、1)；
DMA_configTransfer (DMA_CH6_BASE、传输、0、0)；
→如上所述、将源地址修复到 eCAP2Regs_CAP1。
→对于 CAP1~CAP4、直接从 CCS 分配值。

//###########################################################################
//
// FILE:   dma_ex1_gsram_transfer.c
//
// TITLE:  DMA GSRAM Transfer
//
//! \addtogroup driver_example_list
//! <h1>DMA GSRAM Transfer (dma_ex1_gsram_transfer)</h1>
//!
//!  This example uses one DMA channel to transfer data from a buffer in
//!  RAMGS0 to a buffer in RAMGS1. The example sets the DMA channel
//!  PERINTFRC bit repeatedly until the transfer of 16 bursts (where each
//!  burst is 8 16-bit words) has been completed. When the whole transfer is
//!  complete, it will trigger the DMA interrupt.
//!
//!  \b Watch \b Variables \n
//!  - \b sData - Data to send
//!  - \b rData - Received data
//!
//
//###########################################################################
// $TI Release: F2837xS Support Library v3.12.00.00 $
// $Release Date: Fri Feb 12 19:06:50 IST 2021 $
// $Copyright:
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// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "driverlib.h"
#include "device.h"

//
// DMA data sections
//
#pragma DATA_SECTION(sData, "ramgs0");  // map the TX data to memory
#pragma DATA_SECTION(rData, "ramgs1");  // map the RX data to memory

//
// Defines
//
#define BURST       8       // write 8 to the register for a burst size of 8
#define TRANSFER    16      // [(MEM_BUFFER_SIZE/(BURST)]

//
// Globals
//
uint16_t sData[128];   // Send data buffer
uint16_t rData[128];   // Receive data buffer
volatile uint16_t done;

//
// Function Prototypes
//
__interrupt void dmaCh6ISR(void);
void initDMA(void);
void error();

//
// Main
//
void main(void)
{
    uint16_t i;

    //
    // Initialize device clock and peripherals
    //
    Device_init();

    //
    // Disable pin locks and enable internal pullups.
    //
    //Device_initGPIO(); //skipped for this example

    //
    //Initialize PIE and clear PIE registers. Disables CPU interrupts
    //
    Interrupt_initModule();

    //
    //Initialize the PIE vector table with pointers to the shell Interrupt
    //Service Routines (ISR)
    //
    Interrupt_initVectorTable();

    //
    // Interrupts that are used in this example are re-mapped to
    // ISR functions found within this file.
    //
    Interrupt_register(INT_DMA_CH6, &dmaCh6ISR);

    //
    // Initialize the Device Peripherals:
    //
    initDMA();  // set up the dma

    //
    // User specific code, enable interrupts:
    // Initialize the data buffers
    //
    for(i = 0; i < 128; i++)
    {
        sData[i] = i;
        rData[i] = 0;
    }

    //
    // Enable interrupts required for this example
    //
    Interrupt_enable(INT_DMA_CH6);
    EINT;                                // Enable Global Interrupts
    // Start DMA channel
    DMA_startChannel(DMA_CH6_BASE);

    done = 0;           // Test is not done yet

    while(!done)        // wait until the DMA transfer is complete
    {
       DMA_forceTrigger(DMA_CH6_BASE);

       DEVICE_DELAY_US(1000);
    }

    //
    // When the DMA transfer is complete the program will stop here
    //
    ESTOP0;
}

//
// error - Error Function which will halt the debugger
//
void error(void)
{
    ESTOP0;  //Test failed!! Stop!
    for (;;);
}

//
// dma_init - DMA setup for both TX and RX channels.
//
void initDMA()
{
    //
    // Refer to dma.c for the descriptions of the following functions.
    //

    //
    //Initialize DMA
    //
    DMA_initController();

    const void *destAddr;
    const void *srcAddr;
//    srcAddr = (const void *)sData;
    //add eCAP
    srcAddr = (const void *)(ECAP2_BASE + 4);
    destAddr = (const void *)rData;

    //
    // configure DMA CH6
    //
    DMA_configAddresses(DMA_CH6_BASE, destAddr, srcAddr);
//    DMA_configBurst(DMA_CH6_BASE,BURST,1,1);
//    DMA_configTransfer(DMA_CH6_BASE,TRANSFER,1,1);
    //add eCAP
    DMA_configBurst(DMA_CH6_BASE,BURST,0,1);
    DMA_configTransfer(DMA_CH6_BASE,TRANSFER,0,0);
    DMA_configMode(DMA_CH6_BASE,DMA_TRIGGER_SOFTWARE, DMA_CFG_ONESHOT_DISABLE);
    DMA_setInterruptMode(DMA_CH6_BASE,DMA_INT_AT_END);
    DMA_enableTrigger(DMA_CH6_BASE);
    DMA_enableInterrupt(DMA_CH6_BASE);
}

//
// local_D_INTCH6_ISR - DMA Channel6 ISR
//
__interrupt void dmaCh6ISR(void)
{
    uint16_t i;

    DMA_stopChannel(DMA_CH6_BASE);
    // ACK to receive more interrupts from this PIE group
    EALLOW;
    Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP7);
    EDIS;

    for( i = 0; i < 128; i++ )
    {
        //
        // check for data integrity
        //
        if (rData[i] != i)
        {
            error();
        }
    }

    done = 1; // Test done.
    return;
}

//
// End of file
//

Q2：DMA 可以执行 eCAP2计数器清除处理等吗？

目前、eCAP2 CPU 中断进程执行 eCAP2计数器清除处理等
最终目标是在 eCAP 检测到4个边沿时启动 DMA、然后重新启动 eCAP。 毕竟、如果有必要使用 DMA 传输完成中断并在 CPU 上采取措施、则不值得使用 DMA。
如果 CPU 需要使用 DMA 传输完成中断采取操作、则使用 DMA 没有意义、因此我们打算使用 eCAP 中断。

此致、
还可以