KL46的串口0DMA发送

shock · 发表于 2015-4-3 10:13:15

本帖最后由 shock 于 2015-4-3 10:18 编辑

请教一个kl46dma串口发送的问题，配置为UART0_TX触发DMA发送，参考了http://community.freescale.com/docs/DOC-99476此文档说的是关于kl26的uart0_dma发送，不知道跟kl46是不是有区别。程序配置如下：
uint8_t sData[64];
int main(void)
{
UART_QuickInit(UART0_RX_PA01_TX_PA02, 115200);
for(i=0;i<ARRAY_SIZE(sData);i++)
{
      sData = i;
}
UART0->C5 |= UART0_C5_TDMAE_MASK;                   // Turn on DMA request(Transmit) for UART0
DMA_InitTypeDef DMA_InitStruct1 = {0};

DMA_InitStruct1.chl = HW_DMA_CH0;
DMA_InitStruct1.chlTriggerSource = UART0_TRAN_DMAREQ;
DMA_InitStruct1.transferByteCnt = sizeof(sData);
DMA_InitStruct1.triggerSourceMode = kDMA_TriggerSource_Normal;
DMA_InitStruct1.sMod = kDMA_ModuloDisable;
DMA_InitStruct1.sAddrIsInc = 1;
DMA_InitStruct1.sDataWidth = kDMA_DataWidthBit_8;
DMA_InitStruct1.sAddr = (uint32_t)sData;

DMA_InitStruct1.dMod = kDMA_ModuloDisable;
DMA_InitStruct1.dAddrIsInc = 0;
DMA_InitStruct1.dDataWidth = kDMA_DataWidthBit_8;
DMA_InitStruct1.dAddr = (uint32_t)&UART0->D;

DMA_Init(&DMA_InitStruct1);
DMA_EnableRequest(HW_DMA_CH0);
//             DMA_CallbackInstall(HW_DMA_CH0, DMA_ISR);
//             DMA_ITConfig(HW_DMA_CH0, kDMA_IT_Major, true);

while(1)
{
//                               DMAMUX0->CHCFG[0] &= ~DMAMUX_CHCFG_ENBL_MASK;
                              DMA0->DMA[HW_DMA_CH0].DSR_BCR |= DMA_DSR_BCR_DONE_MASK;             //Clear Done bit
                              DMA0->DMA[HW_DMA_CH0].DSR_BCR = DMA_DSR_BCR_BCR(sizeof(sData));    //Reset BCR
                              DMA0->DMA[HW_DMA_CH0].SAR  = (uint32_t)sData;       //设置源地址，如果不设置，地址会一直增加
                              DMA_EnableRequest(HW_DMA_CH0);
//                               DMAMUX0->CHCFG[0] |= DMAMUX_CHCFG_ENBL_MASK;
                              GPIO_ToggleBit(HW_GPIOB, 23);
                              DelayMs(1000);
}
}
现发现一个问题，就是当dma串口发送的时候，源地址为0x2000003C，然后发送完64个字节后，源地址变为0x2000007C，且下次发送是从0x2000007C开始发，发送完之后，源地址又变成0x200000AC，导致数据发送错误，因此在下次使能发送前，设置地址，红色那句，但是这样应该不算解决问题吧，是不是哪里配置错了，求FAE线上支持解答，谢谢！！ SMOD DMOD.png

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shock · 发表于 2015-4-3 10:17:43

本帖最后由 shock 于 2015-4-3 10:34 编辑

还有一个问题，就是关于DMA->DCR寄存器中的SMOD和DMOD，应该是指循环的字节个数吧，但是如何使用呢，我将SMOD和DMOD设置为64字节后，地址是不会递增了，但是数据却是错误的。发送的数据一直是<---- 接收帧：00 00 00 00 00 0E 27 07 78 00 00 00 C0 D4 01 00 00 A0 06 40 00 B0 06 40 00 C0 06 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00，搞不灵清

安 · 发表于 2015-4-3 11:31:14

应该用SMOD,这个达到最大值以后会自动恢复到源地址.我发送的时候一般不用DMA,因为每次发送的数据都不一样.

shock · 发表于 2015-4-3 11:55:13

安发表于 2015-4-3 11:31
应该用SMOD,这个达到最大值以后会自动恢复到源地址.我发送的时候一般不用DMA,因为每次发送的数据都不一样. ...

你好，我就将smod设置为64字节，发现传输的数据错误，虽然地址还是源地址。
另外就是dma可以发送不一样的数据的啊，你可以将数组赋值，此时再使能dma实现发送

FSL_TICS_ZP · 发表于 2015-4-3 15:54:13

shock 发表于 2015-4-3 11:55
你好，我就将smod设置为64字节，发现传输的数据错误，虽然地址还是源地址。
另外就是dma可以发送不一样的 ...

安建议是正确的，最好使用SMOD的功能，我贴上使用SMOD的测试函数，你可以参考一下。

/*******************************************************************************
* This function will perform the basic transfer using a DMA SMOD feature and
* using software start and will check for errors in transmission, if any.
* Points to note:
* - SMOD size should be equal to the buffer_size defined
* - data size defined for src and dest xfr should be same
* as the MEM_FILL_* enum called.
*
* Result: This is validated by checking if the data at same source address is
* taken to be copied to destination address
* i.e Source address is wrapped after SMOD boundary.
*
* For eg:
* SMOD =32 bytes
* nbytes=64 bytes
*
* 0 32 64
* SADDR: |-------------------|-------------------|
* <-------data x-----><-------data y------>
*
* 0 32 64
* DADDR: |-------------------|-------------------|
* <-------data x-----><-------data x------>
*
******************************************************************************/
void dma_smod(void)
{
int dma_ch, loop_count;
uint32 dest_addr;
uint32 buffer_size;
uint32 Nbytes = 64; //=16*4
//uint32 Nbytes = 128; //=64*2
//uint32 Nbytes = 256; //=64*4
//uint32 Nbytes = 1024; //512*2
//uint32 Nbytes = 4096; //2K*2
//uint32 Nbytes = 8192; //4K*2 L2K has 16K Sram, 0x1FFFF000 - 0x20003000, so SMOD < 9
printf("\n DMA transfer test using SMOD feature.");
/* Initialize test variables */
tcd.saddr = SRAM_SADDRESS;
tcd.daddr = SRAM_DADDRESS;
tcd.nbytes = Nbytes;
tcd.ctrl = DMA_DCR_SSIZE_LONGWORD //long word transfer
| DMA_DCR_SINC_MASK
| DMA_DCR_DSIZE_LONGWORD //long word transfer
| DMA_DCR_DINC_MASK
| DMA_DCR_SMOD(0x1); //circular buffer size of 16 bytes
//| DMA_DCR_SMOD(0x3); //circular buffer size of 64 bytes
//| DMA_DCR_SMOD(0x6); //circular buffer size of 512 bytes
//| DMA_DCR_SMOD(0x8); //circular buffer size of 2K bytes
//| DMA_DCR_SMOD(0x9); //circular buffer size of 4K bytes
/* Note: This is simple DMA transfer, so Auto Align and interrupt
* are not used.
* Also, if AA is enabled, DINC and SINC will increase no matter
* what value they have */
/* Note: For this test the no of bytes to be xfred must be evenly divisible
* by the buffer_size; else the for loop used to check the end results,
* will not work correctly */
/* Size of the circular source buffer, Must be a power of 2 and should be
* equal to SMOD size. */
buffer_size = 16; //0x10
//buffer_size = 64; //0x40
//buffer_size = 512; //0x200
//buffer_size = 2048; //0x800
//buffer_size = 4096; //0x1000 P0FC has 16K Sram, 0x1FFFE000 - 0x20002000, so SMOD < 9
/* Use all 4 DMA channels to check the basic transmission of data */
for(dma_ch = 0; dma_ch < 4; dma_ch++)
{
/* Initialize data at source location */
for(int j = 0; j < buffer_size; j++)
*((uint8 *)(tcd.saddr + j)) = j + dma_ch;
tcd.channelno = dma_ch;
/* Clear status */
DMA_DSR_BCR(dma_ch) |= DMA_DSR_BCR_DONE_MASK;
/* Configure DMA registers */
dma_config(CONFIG_BASIC_XFR,&tcd);
/* Start DMA transmission */
dma_config(DMA_SOFT_START, &tcd);
/* Wait till transfer is done */
dma_config(XFR_OVER_WAIT, &tcd);
/* Check data coherence */
dest_addr = tcd.daddr;
for(loop_count = 0; loop_count < (Nbytes/buffer_size); loop_count++)
{
tcd.daddr = dest_addr + (loop_count * buffer_size) ;
tcd.nbytes = buffer_size;
dma_config(CMP_MEM, &tcd);
}
tcd.daddr = dest_addr;
tcd.nbytes = Nbytes;
printf("\nDMA channel %01x test complete.\n", dma_ch);
printf("\n Press a character to proceed to next DMA CHANNEL...");
in_char();
}
if(dma_error)
{
printf("\nTESTCASE FAIL\r\n");
}
else
{
printf("\nTESTCASE PASS\r\n");
}
}