2018年10月20日 | STM 32 之can 实例+代码解析

#include "sysdef.h"

#define MAX_MAIL_NUM 3

//CAN总线调试:0=运行 1=自环调试

#define CAN_DEBUG 0

//CAN总线波特率:0=250kbps,1=500kbps,2=1Mbps

#define CAN1_BPS 0

unsigned char can1_addr = 0;

unsigned short Can1_Tx_Count =0;

unsigned short Can1_Rx_Count =0;

unsigned short Can1_Send_Delay =0;

unsigned char Can1_Send_Buf[10]={0xeb,0x90,0x01,0x55,0xAA};

unsigned char Can1_Recv_Buf[10]={0};

extern int angle_num ;

extern unsigned int angle_data ;

static u8 CAN_msg_num[MAX_MAIL_NUM]; // 发送邮箱标记

void CAN1_Config_init(void)

{

CAN_InitTypeDef CAN_InitStructure;

CAN_FilterInitTypeDef CAN_FilterInitStructure;

CAN_DeInit(CAN1);

CAN_StructInit(&CAN_InitStructure);

//36MHz 500Kbps

CAN_InitStructure.CAN_TTCM=DISABLE;//禁止时间触发通信模式

CAN_InitStructure.CAN_ABOM=DISABLE;//软件对CAN_MCR寄存器的INRQ位进行置1随后清0后,一旦硬件检测

//到128次11位连续的隐性位,就退出离线状态

CAN_InitStructure.CAN_AWUM=DISABLE;//睡眠模式通过清除CAN_MCR寄存器的SLEEP位,由软件唤醒

CAN_InitStructure.CAN_NART=DISABLE;//CAN报文是否只发1次,不管发送的结果如何(成功/出错或仲裁丢失)

CAN_InitStructure.CAN_RFLM=DISABLE;//在接收到溢出时FIFO未被锁定,当接收到FIFO报文未被读出,下一个收到的报文会覆盖原有的报文

CAN_InitStructure.CAN_TXFP=DISABLE;//发送的FIFO优先级由报文的标识符来决定

#if CAN_DEBUG

CAN_InitStructure.CAN_Mode= CAN_Mode_LoopBack;

#else

CAN_InitStructure.CAN_Mode= CAN_Mode_Normal;

#endif

//传输波特率

if(CAN1_BPS == 0)

{

CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;//重新同步跳跃宽度1个时间单位

CAN_InitStructure.CAN_BS1=CAN_BS1_12tq;//时间段1为9个时间单位

CAN_InitStructure.CAN_BS2=CAN_BS2_3tq;//时间段2为8个时间单位

CAN_InitStructure.CAN_Prescaler= 9;//36M/(1+12+3)/9= 250kbps

//36M/(1+5+2)/9 = 500kbps

//36M(1+2+1)/9 = 1M

}

else if(CAN1_BPS == 1)

{

CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;//重新同步跳跃宽度1个时间单位

CAN_InitStructure.CAN_BS1=CAN_BS1_5tq;//时间段1为9个时间单位

CAN_InitStructure.CAN_BS2=CAN_BS2_2tq;//时间段2为8个时间单位

CAN_InitStructure.CAN_Prescaler= 9;//36M/(1+12+3)/9= 250kbps

}

else

{

CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;//重新同步跳跃宽度1个时间单位

CAN_InitStructure.CAN_BS1=CAN_BS1_2tq;//时间段1为9个时间单位

CAN_InitStructure.CAN_BS2=CAN_BS2_1tq;//时间段2为8个时间单位

CAN_InitStructure.CAN_Prescaler= 9;//36M/(1+12+3)/9= 250kbps

}

CAN_Init(CAN1,&CAN_InitStructure);

CAN_FilterInitStructure.CAN_FilterNumber=0; //指定了待初始化的过滤器0

CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;//指定了过滤器将被初始化到的模式为标识符屏蔽位模式

CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;;//给出了过滤器位宽1个32位过滤器

CAN_FilterInitStructure.CAN_FilterIdHigh=0x0000;//用来设定过滤器标识符（32位位宽时为其高段位，16位位宽时为第一个）

CAN_FilterInitStructure.CAN_FilterIdLow=0x0000;;//用来设定过滤器标识符（32位位宽时为其低段位，16位位宽时为第二个)

CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0x0000;//用来设定过滤器屏蔽标识符或者过滤器标识符（32位位宽时为其高段位，16位位宽时为第一个)

CAN_FilterInitStructure.CAN_FilterMaskIdLow=0x0000;//用来设定过滤器屏蔽标识符或者过滤器标识符（32位位宽时为其低段位，16位位宽时为第二个)

CAN_FilterInitStructure.CAN_FilterFIFOAssignment=CAN_FIFO0;;//设定了指向过滤器的FIFO0

CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;//使能过滤器

CAN_FilterInit(&CAN_FilterInitStructure);

}

// ***************************************************************

// BaudRate = 1 / NominalBitTime

// NominalBitTime = 1tq + tBS1 + tBS2

// tq = (BRP[9:0] + 1) x tPCLK

// tPCLK = CAN's clock = APB1's clock

// 1Mbps 速率下，采用点的位置在6tq位置处，BS1=5, BS2=2

// 500kbps 速率下，采用点的位置在8tq位置处，BS1=7, BS2=3

// 250kbps 速率下，采用点的位置在14tq位置处，BS1=13, BS2=2

// 125k, 100k, 50k, 20k, 10k 的采用点位置与 250K 相同

// ****************************************************************

void CAN1_Com_init(void)

{

GPIO_InitTypeDef GPIO_InitStruct;

NVIC_InitTypeDef NVIC_InitStructure;

NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel = USB_HP_CAN1_TX_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX1_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

//Can Rx

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_11;

GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IPU;

GPIO_Init(GPIOA,&GPIO_InitStruct);

//Can Tx

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_12;

GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_Init(GPIOA,&GPIO_InitStruct);

CAN1_Config_init();

CAN_ITConfig(CAN1,CAN_IT_FMP0 | CAN_IT_FF0 | CAN_IT_FOV0, ENABLE); // fifo0中断

CAN_ITConfig(CAN1,CAN_IT_FMP1 | CAN_IT_FF1 | CAN_IT_FOV1, ENABLE); // fifo1中断

CAN_ITConfig(CAN1,CAN_IT_TME, DISABLE); // 发送中断

CAN_ITConfig(CAN1,CAN_IT_EWG | CAN_IT_EPV | CAN_IT_BOF | CAN_IT_LEC | CAN_IT_ERR | CAN_IT_WKU | CAN_IT_SLK, ENABLE); // ERR中断

// CAN缓存初始化

memset(CAN_msg_num,0,MAX_MAIL_NUM);

}

int CAN1_Tx_msg(CanTxMsg TxMessage)

{

u8 TransmitMailbox = 0;

TransmitMailbox = CAN_Transmit(CAN1,&TxMessage);

if(CAN_NO_MB == TransmitMailbox)

{

//发送失败

return 0;

}

else

{

CAN_msg_num[TransmitMailbox] = 1;

}

CAN_ITConfig(CAN1,CAN_IT_TME, ENABLE);

return 1;

}

u16 angle=0,angle_h=0,angle_l=0;

extern unsigned char angle_dir;

int CAN1_Tx_data(void)

{

CanTxMsg TxMessage;

u8 TransmitMailbox = 0,i=0;

TxMessage.StdId=0x6f1;//设定标准标识符

TxMessage.ExtId=0x1234;//设置扩展标识符

TxMessage.RTR=CAN_RTR_DATA;//设定待传输消息的帧类型

TxMessage.IDE=CAN_ID_STD;//设定消息标识符的类型

TxMessage.DLC=6; //数据长度

angle=angle_data/10;

if(angle>9999) angle=9999;

angle_h=angle/100;

angle_h=angle_h/10*16+angle_h;

angle_l=angle0;

angle_l=angle_l/10*16+angle_l;

Can1_Send_Buf[0]=angle_num; //圈数

Can1_Send_Buf[1]=angle_h; //总角度

Can1_Send_Buf[2]=angle_l;

Can1_Send_Buf[3]=0;

Can1_Send_Buf[4]=0;

Can1_Send_Buf[5]=angle_dir;

for(i=0;i < TxMessage.DLC;i++)

{

TxMessage.Data[i] = Can1_Send_Buf[i];

}

TransmitMailbox = CAN_Transmit(CAN1,&TxMessage);

if(CAN_NO_MB == TransmitMailbox)

{

//发送失败,没有空邮箱

return 0;

}

else

{

CAN_msg_num[TransmitMailbox] = 1;

}

CAN_ITConfig(CAN1,CAN_IT_TME, ENABLE);

Can1_Tx_Count++;

if(Can1_Tx_Count > 10000)

Can1_Tx_Count =0;

Can1_Send_Delay =200;

return 1;

}

//解析数据

void CAN1_Rx_Data(CanRxMsg RxMessage)

{

u8 i =0;

if((RxMessage.StdId==0x6f1) && (RxMessage.IDE==CAN_ID_STD) && ((RxMessage.Data[1]|RxMessage.Data[0]<<8)==0xEB90))

{

for(i=0;i < RxMessage.DLC;i++)

{

Can1_Recv_Buf[i] = RxMessage.Data[i];

}

Can1_Rx_Count++;

if(Can1_Rx_Count > 10000)

Can1_Rx_Count =0;

}

}

//发送完中断函数

void CAN1_Send(void)

{

if(CAN_msg_num[0])

{

if(CAN_GetITStatus(CAN1,CAN_IT_RQCP0))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_RQCP0);

CAN_ITConfig(CAN1,CAN_IT_TME, DISABLE);

CAN_msg_num[0] = 0;

}

}

if(CAN_msg_num[1])

{

if(CAN_GetITStatus(CAN1,CAN_IT_RQCP1))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_RQCP1);

CAN_ITConfig(CAN1,CAN_IT_TME, DISABLE);

CAN_msg_num[1] = 0;

}

}

if(CAN_msg_num[2])

{

if(CAN_GetITStatus(CAN1,CAN_IT_RQCP2))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_RQCP2);

CAN_ITConfig(CAN1,CAN_IT_TME, DISABLE);

CAN_msg_num[2] = 0;

}

}

}

//接收中断函数

void CAN1_Recv(unsigned char num)

{

CanRxMsg RxMessage;

switch(num)

{

case 0:

if(CAN_GetITStatus(CAN1,CAN_IT_FF0))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_FF0);

}

else if(CAN_GetITStatus(CAN1,CAN_IT_FOV0))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_FOV0);

}

else

{

CAN_Receive(CAN1,CAN_FIFO0, &RxMessage);

//解析数据:

CAN1_Rx_Data(RxMessage);

}

break;

case 1:

if(CAN_GetITStatus(CAN1,CAN_IT_FF1))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_FF1);

}

else if(CAN_GetITStatus(CAN1,CAN_IT_FOV1))

{

CAN_ClearITPendingBit(CAN1,CAN_IT_FOV1);

}

else

{

CAN_Receive(CAN1,CAN_FIFO1, &RxMessage);

//解析数据

CAN1_Rx_Data(RxMessage);

}

break;

}

}

void CAN1_Main(unsigned char flg )

{

if(flg)

{

if(Can1_Send_Delay == 0)

CAN1_Tx_data();

}

}