DMA串口接收数据的问题

XUKAI · 发表于 2014-10-18 14:21:16

原子哥求助关于DMA。

u16 DMA1_MEM_LEN;

void MYDMA_ConfigCH6(u32 cpar,u32 cmar,u16 cndtr)
{
RCC->AHBENR|=1<<0;   //????DMA1?±??
delay_ms(3);    //????DMA?±?????¨
DMA1_Channel6->CPAR=cpar; //DMA1 ???è???·
DMA1_Channel6->CMAR=(u32)cmar; //DMA1,?????÷???·
DMA1_MEM_LEN=cndtr;      //±???DMA??????????
DMA1_Channel6->CNDTR=cndtr;    //DMA1,??????????
DMA1_Channel6->CCR=0X00000000; //????
DMA1_Channel6->CCR&=~(1<<4);   //???????÷?? ???????????è??
DMA1_Channel6->CCR|=1<<5;   //                ????????·????
DMA1_Channel6->CCR|=0<<6;   //???è???··?????????
DMA1_Channel6->CCR|=1<<7; //?????÷????????
DMA1_Channel6->CCR|=0<<8; //???è?????í????8??
DMA1_Channel6->CCR|=0<<10;   //?????÷?????í??8??
DMA1_Channel6->CCR|=1<<12;   //??????????
DMA1_Channel6->CCR|=0<<14;   //·??????÷???????÷????
DMA1_Channel6->CCR|=1<<0;     //????DMA??????
}
//????????DMA????
void MYDMA_Enable(DMA_Channel_TypeDef*DMA_CHx)
{
DMA_CHx->CCR&=~(1<<0);       //??±?DMA????
DMA_CHx->CNDTR=DMA1_MEM_LEN; //DMA1,??????????
DMA_CHx->CCR|=1<<0;          //????DMA????
}

//?®??2??????
void USART2_Config(void)   //?????? ????USART2
{
GPIO_InitTypeDef    GPIO_InitStructure;    //?®???????????á????±???
USART_InitTypeDef   USART_InitStructure;   //?®???????????á????±???

//???? USART2 ?±??
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE); //?ò???®???????±??
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); //?ò??PA?????±??

//??USART2 Tx?¨·??????©??GPIO?????????ì????????
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;      //???¨????IO?? ?????¨PA2
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;           //???????ì????
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    //?è?¨IO??????????????50MHz
GPIO_Init(GPIOA, &GPIO_InitStructure);          //??????GPIOA

//??USART2 Rx?¨???????©??GPIO??????????????????
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;      //???¨????IO?? ?????¨PA3
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;   //????????
//GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //???????
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);                    //??????GPIOA

//????USART2????
USART_InitStructure.USART_BaudRate = 115200;                     //?¨?????è????115200
USART_InitStructure.USART_WordLength = USART_WordLength_8b;     //?????????è????8??
USART_InitStructure.USART_StopBits = USART_StopBits_1;          //???????è????1??
USART_InitStructure.USART_Parity = USART_Parity_No ;            //??·????????é????
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; //?????÷?????????è????????????
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //??????·?????????
USART_Init(USART2, &USART_InitStructure);                       //??????USART2

//?ò??·?????????????????(?????è??????)
//USART_ITConfig(USART2, USART_IT_TXE, ENABLE); // ???????¨??USART2·???????
// USART_ITConfig(USART2, USART_IT_RXNE, ENABLE); // ???????¨??USART2????????

//???? USART2?? ?????ê±?
USART_Cmd(USART2, ENABLE); // USART2????

//??????????????1??×?????·¨???··?????????????
// USART_ClearFlag(USART2, USART_FLAG_TC); //???®??2·???±ê??
}

int main(void)
{
delay_init(); //???±??????????
OLED_Init();   //??????OLED
  OLED_ShowString(0,0, " x aixs:   ");
  OLED_ShowString(0,16," y aixs:   ");
  OLED_ShowString(0,32," z axis:   ");
  OLED_ShowString(0,48," speed: ");

OLED_Refresh_Gram();
TIM3_PWM_Init(899,0);//??·?????PWM????=72000/(899+1)=80Khz 899×??ó
USART2_Config();//?®????????

USART2->CR3|=1<<6;//????DMA ?®????????
MYDMA_ConfigCH6((u32)&USART2->DR,(u32)Re_buf,12);
while(1)
{

  if(Re_buf[3]!=0)
  OLED_ShowNum(103,48,Re_buf[3],3,16);
  OLED_Refresh_Gram();

if(Re_buf[0]==0x55)       //?ì?é???·
         {
            switch(Re_buf[1])
            {
               case 0x51: //±ê??????°ü????????°ü
                  a[0] = ((short)(Re_buf[3]<<8 | Re_buf[2]))/32768.0*16; //CESHI     //X?á??????
                  a[1] = ((short)(Re_buf[5]<<8 | Re_buf[4]))/32768.0*16;      //Y?á??????
                  a[2] = ((short)(Re_buf[7]<<8 | Re_buf[6]))/32768.0*16;      //Z?á??????
                  T    = ((short)(Re_buf[9]<<8 | Re_buf[8]))/340.0+36.25;      //????
                  break;
               case 0x52: //±ê??????°ü????????°ü
                  w[0] = ((short)(Re_buf[3]<<8| Re_buf[2]))/32768.0*2000;      //X?á??????
                  w[1] = ((short)(Re_buf[5]<<8| Re_buf[4]))/32768.0*2000;      //Y?á??????
                  w[2] = ((short)(Re_buf[7]<<8| Re_buf[6]))/32768.0*2000;      //Z?á??????
                  T    = ((short)(Re_buf[9]<<8| Re_buf[8]))/340.0+36.25;      //????
                  break;
               case 0x53: //±ê??????°ü??????°ü
                  angle[0] = ((short)(Re_buf[3]<<8| Re_buf[2]))/32768.0*180;   //X?á??×????¨x ?á?©
                  angle[1] = ((short)(Re_buf[5]<<8| Re_buf[4]))/32768.0*180;   //Y?á?©?????¨y ?á?©
                  angle[2] = ((short)(Re_buf[7]<<8| Re_buf[6]))/32768.0*180;   //Z?á???????¨z ?á?©
                  T        = ((short)(Re_buf[9]<<8| Re_buf[8]))/340.0+36.25;   //????

                  //printf("X?á??????%.2f   Y?á??????%.2f   Z?á??????%.2f\r\n",angle[0],angle[1],angle[2]);
                  break;
               default: break;
            }
     }

  LEFT_PWM_VAL_Z=300;
  LEFT_PWM_VAL_F=450;
  RIGHT_PWM_VAL_Z=300;
  RIGHT_PWM_VAL_F=450;
}
}

这么配置串口2，有没有错？oled没有显示到数据，调了几天了。

chris_w · 发表于 2014-10-18 17:31:20

注释好乱&_&

XUKAI · 发表于 2014-10-18 19:03:06

回复【2楼】chris_w:
---------------------------------
程序粘贴过来，注释就乱码了，有一处要更正一下，MYDMA_ConfigCH6((u32)&USART2->DR,(u32)Re_buf,12);应改为
MYDMA_ConfigCH6((u32)&USART2->DR,(u32)Re_buf,11);