STM can的问题，loopback模式，cantx波形是这样，说明了什么？

只看该作者 · 2011-7-23 12:57

搞了很久了，改成正常模式后，数据好像一直发不出去，但是loopback模式能收发成功，可是管脚上就是没什么信号，文档里说会有的。我把收发器拆掉了，应该不是硬件问题。

只看该作者 · 2011-7-23 13:07

搞定了，草他码得，是芯片坏了，草

只看该作者 · 2011-7-23 13:55

本帖最后由相信哥咯于 2011-7-23 13:58 编辑

用了一段时间好像又没波形了？？？
重启重烧也没了。

只看该作者 · 2011-7-23 15:41

本帖最后由相信哥咯于 2011-7-23 15:43 编辑

----------------------------------
我快被它搞残了
------------------------------------------
main()
{
      unsigned int a;
      RCC_Configuration();
                     /*初始化 GPIOC时钟*/
//  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
USART_Configuration();
Delay(10);
CAN_configure();
  // LedInit();

while(1)
{
               //CAN_ClearFlag(CAN_FLAG_BOF);
               GPIO_SetBits(GPIOB,GPIO_Pin_7);
            Delay(10);
            GPIO_ResetBits(GPIOB,GPIO_Pin_7);
            Delay(10);
            GPIO_SetBits(GPIOB,GPIO_Pin_7);
            Delay(10);
            GPIO_ResetBits(GPIOB,GPIO_Pin_7);
            Delay(10);
            can_send(0x57);
            a=can_rev();
            USART1_Putc(a);

}

}

--------------------------------------------------------------------------------------------------
#include"stm32f10x_lib.h"
void CAN_configure(void)
{
               u8 wrong;
               CAN_InitTypeDef CAN_InitStructure;
            CAN_FilterInitTypeDef CAN_FilterInitStructure;
            GPIO_InitTypeDef GPIO_InitStructure;

      //       RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO , ENABLE);
      //       RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
      //       RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN, ENABLE);

         /* Configure CAN pin: RX */
               GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
               GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
               GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
               GPIO_Init(GPIOA, &GPIO_InitStructure);

      /* Configure CAN pin: TX */
               GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
               GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
            GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
               GPIO_Init(GPIOA, &GPIO_InitStructure);


      /*can register int*/
            CAN_DeInit();
            CAN_StructInit(&CAN_InitStructure);

      /*can cell init*/


               CAN_InitStructure.CAN_TTCM=DISABLE;
               CAN_InitStructure.CAN_ABOM=DISABLE;
               CAN_InitStructure.CAN_AWUM=DISABLE;
               CAN_InitStructure.CAN_NART=DISABLE;
               CAN_InitStructure.CAN_RFLM=DISABLE;
               CAN_InitStructure.CAN_TXFP=DISABLE;
               CAN_InitStructure.CAN_Mode=CAN_Mode_LoopBack;
               CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;
               CAN_InitStructure.CAN_BS1=CAN_BS1_8tq;
               CAN_InitStructure.CAN_BS2=CAN_BS2_7tq;
               CAN_InitStructure.CAN_Prescaler=5;
               wrong=CAN_Init(&CAN_InitStructure);
               while(wrong==CANINITFAILED){}

/* CAN filter init */
               CAN_FilterInitStructure.CAN_FilterNumber=0;
               CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;
               CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
               CAN_FilterInitStructure.CAN_FilterIdHigh=0x0000;//((u32)0x0020<<21)>>16;//标识符
               CAN_FilterInitStructure.CAN_FilterIdLow=0x0000;//(((u32)0x0020<<21)|CAN_ID_STD|CAN_RTR_DATA);//
               CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0x0000;
               CAN_FilterInitStructure.CAN_FilterMaskIdLow=0x0000;
               CAN_FilterInitStructure.CAN_FilterFIFOAssignment=0;;
               CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
               CAN_FilterInit(&CAN_FilterInitStructure);
         //       CAN_ITConfig(CAN_IT_FMP0, ENABLE);

}

void can_send(unsigned char data)
{

            CanTxMsg TxMessage;
            u8 TransmitMailbox = 0;
            TxMessage.StdId=0x0020;//标识符
               TxMessage.RTR=CAN_RTR_DATA;
               TxMessage.IDE=CAN_ID_STD;
               TxMessage.DLC=2;
               TxMessage.Data[0]=data;
               TxMessage.Data[1]=0xFE;

               TransmitMailbox=CAN_Transmit(&TxMessage);
               while(CAN_TransmitStatus(TransmitMailbox) != CANTXOK){}//等待发送

}

unsigned char can_rev(void)
{
               CanRxMsg RxMessage;

               RxMessage.StdId=0x11;//不需要设置
               RxMessage.IDE=CAN_ID_STD;
               RxMessage.DLC=2;
               RxMessage.Data[0]=0x00;
               RxMessage.Data[1]=0x00;
               while (CAN_MessagePending(CAN_FIFO0)==0);//等到接收

               CAN_Receive(CAN_FIFO0, &RxMessage);
            CAN_FIFORelease(CAN_FIFO0);

  return RxMessage.Data[0];
}

-------------------------------------------------------------------------------------------------
void RCC_Configuration(void)

{
//***
  ErrorStatus HSEStartUpStatus;

  //***

//* system clocks configuration -----------------系统时钟配置-------------------///

//* RCC system reset(for debug purpose) //

RCC_DeInit();                                  //将外设RCC寄存器重设为缺省值

//* Enable HSE *

RCC_HSEConfig(RCC_HSE_ON);                   //开启外部高速晶振（HSE）

//* Wait till HSE is ready /


HSEStartUpStatus = RCC_WaitForHSEStartUp(); //等待HSE起振

if(HSEStartUpStatus == SUCCESS)             //若成功起振，（下面为系统总线时钟设置）

{

//* Enable Prefetch Buffer /

FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); //使能FLASH预取指缓存

//* Flash 2 wait state /

FLASH_SetLatency(FLASH_Latency_2); //设置FLASH存储器延时时钟周期数(根据不同的系统时钟选取不同的值)

//* HCLK = SYSCLK /

  RCC_HCLKConfig(RCC_SYSCLK_Div1); //设置AHB时钟=72 MHz

//* PCLK2 = HCLK/2 /

RCC_PCLK2Config(RCC_HCLK_Div2); //设置APB1时钟=36 MHz(APB1时钟最大值)

//* PCLK1 = HCLK/2 /

RCC_PCLK1Config(RCC_HCLK_Div2); //设置APB2时钟=72 MHz

//* Configure ADCCLK such as ADCCLK = PCLK2/2 /

  // RCC_ADCCLKConfig(RCC_PCLK2_Div2); //RCC_PCLK2_Div2,4,6,8

//* PLLCLK = 8MHz * 9 = 72 MHz /

RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9); //PLL必须在其激活前完成配置（设置PLL时钟源及倍频系数）

//* Enable PLL /

RCC_PLLCmd(ENABLE);

//* Wait till PLL is ready /

while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)

{

}

//* Select PLL as system clock source /

RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

//* Wait till PLL is used as system clock source /

while(RCC_GetSYSCLKSource() != 0x08)

{

}

}


  //*****
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
   RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN, ENABLE);

//***/

}