STM32之CAN总线例程

#include "stm32f10x.h"

/* RCC时钟配置 */

void RCC_config(void)

{ 

 ErrorStatus HSEStartUpStatus;

 /* RCC寄存器设置为默认配置 */

 RCC_DeInit();

 /* 打开外部高速时钟 */

 RCC_HSEConfig(RCC_HSE_ON);

 /* 等待外部高速时钟稳定 */

 HSEStartUpStatus = RCC_WaitForHSEStartUp();

 if(HSEStartUpStatus == SUCCESS) 

 { 

  /* 设置HCLK = SYSCLK */

  RCC_HCLKConfig(RCC_SYSCLK_Div1);

  /* 设置PCLK2 = HCLK */

  RCC_PCLK2Config(RCC_HCLK_Div1);

  /* 设置PCLK1 = HCLK / 2 */

  RCC_PCLK1Config(RCC_HCLK_Div2);

//  /* 设置FLASH代码延时 */

//  FLASH_SetLatency(FLASH_Latency_2);

//  /* 使能预取址缓存 */

//  FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);

  /* 设置PLL时钟源为HSE倍频9 72MHz */

  RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);

  /* 使能PLL */

  RCC_PLLCmd(ENABLE);

  /* 等待PLL稳定 */

  while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);

  /* 设置PLL为系统时钟源 */

  RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

  /* 等待系统时钟源切换到PLL */

  while(RCC_GetSYSCLKSource() != 0x08);

 }

}

/* GPIO配置 */

void GPIO_config(void)

{

 GPIO_InitTypeDef GPIO_InitStructure;

 /* 时钟配置 */

 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);

 /* RX */

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;

    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

    GPIO_Init(GPIOA, &GPIO_InitStructure);

 /* TX */

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;

    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

    GPIO_Init(GPIOA, &GPIO_InitStructure);

}

/* 中断嵌套控制器配置 */

void NVIC_config(void)

{

 NVIC_InitTypeDef NVIC_InitStructure;

 /* 选择中断分组2 */

 NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

 /* 设置CAN接收中断 */

 NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;

 NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

 NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;

 NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

 NVIC_Init(&NVIC_InitStructure);

}

/* CAN总线配置 */

void CAN_config(void)

{

 CAN_InitTypeDef CAN_InitStructure;

 CAN_FilterInitTypeDef CAN_FilterInitStructure;

 RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

 /* CAN1默认参数 */

 CAN_DeInit(CAN1);

 /* 将结构体填入默认参数 */

 CAN_StructInit(&CAN_InitStructure);

 /* 关闭时间触发模式 */

 CAN_InitStructure.CAN_TTCM = DISABLE;

 /* 关闭自动离线管理 */

 CAN_InitStructure.CAN_ABOM = ENABLE;

 /* 关闭自动唤醒 */

 CAN_InitStructure.CAN_AWUM = ENABLE;

 /* 自动重传 */

 CAN_InitStructure.CAN_NART = DISABLE;

 /* 禁止FIFO溢出时覆盖原报文 */

 CAN_InitStructure.CAN_RFLM = DISABLE;

 /* 关闭优先级取决于ID */

 CAN_InitStructure.CAN_TXFP = DISABLE;

 /* 正常模式 */

 CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;

 /* 设置波特率 */

 CAN_InitStructure.CAN_SJW = CAN_SJW_2tq;

 CAN_InitStructure.CAN_BS1 = CAN_BS1_6tq;

 CAN_InitStructure.CAN_BS2 = CAN_BS2_3tq;

 CAN_InitStructure.CAN_Prescaler = 4;

 /* 初始化CAN总线 */

 CAN_Init(CAN1, &CAN_InitStructure);

 /* 过滤器配置 */

 CAN_FilterInitStructure.CAN_FilterNumber = 0;

 CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;

 CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;

 CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0020;

 CAN_FilterInitStructure.CAN_FilterIdLow = 0x0007;

 CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x0020;

 CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0x0000;

 CAN_FilterInitStructure.CAN_FilterFIFOAssignment = CAN_Filter_FIFO0;

 CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;

 CAN_FilterInit(&CAN_FilterInitStructure);

 /* 接收挂起中断 */

 CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);

}

/* 毫秒延时函数 */

void delay_ms(uint16_t time)

{    

 uint16_t i = 0; 

 while(time--)

 {

  i = 12000;

  while(i--);    

 }

}

CanTxMsg TxMessage;

/* 主函数 */

int main(void)

{

 uint8_t TransmitMailbox = 0;

 /* RCC时钟配置 */

 RCC_config();

 /* GPIO配置 */

 GPIO_config(); 

 /* CAN总线配置 */

 CAN_config();

 /* 中断嵌套控制器配置 */

 NVIC_config();

 while(1)

 {

        TxMessage.StdId = 1;

        TxMessage.ExtId = 0;

        TxMessage.IDE = CAN_ID_STD;

        TxMessage.RTR = CAN_RTR_DATA;

        TxMessage.DLC = 8;

        TxMessage.Data[0] = 0x11;

        TxMessage.Data[1] = 0x22;

        TxMessage.Data[2] = 0x33;

        TxMessage.Data[3] = 0x44;

        TxMessage.Data[4] = 0x55;

        TxMessage.Data[5] = 0x66;

        TxMessage.Data[6] = 0x77;

        TxMessage.Data[7] = 0x88;

  TransmitMailbox = CAN_Transmit(CAN1, &TxMessage);

  while((CAN_TransmitStatus(CAN1, TransmitMailbox) != CANTXOK));

  delay_ms(1000);

 }

}

void USB_LP_CAN1_RX0_IRQHandler(void)

{

 CanRxMsg RxMessage;

    volatile CanRxMsg Message;

    CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);

    Message.StdId = RxMessage.StdId;

    Message.ExtId = RxMessage.ExtId;

    Message.IDE = RxMessage.IDE;

    Message.RTR = RxMessage.RTR;

    Message.DLC = RxMessage.DLC;

    Message.Data[0] = RxMessage.Data[0];

    Message.Data[1] = RxMessage.Data[1];

    Message.Data[2] = RxMessage.Data[2];

    Message.Data[3] = RxMessage.Data[3];

    Message.Data[4] = RxMessage.Data[4];

    Message.Data[5] = RxMessage.Data[5];

    Message.Data[6] = RxMessage.Data[6];

    Message.Data[7] = RxMessage.Data[7];

}