南京专业网站优化公司,网站备案 超链接,系统开发步骤,甘肃兰州天气预报15天-----CAN1_Mode_Init CAN模式初始化函数:u8 CAN1_Mode_Init(u8 tsjw,u8 tbs2,u8 tbs1,u16 brp,u8 mode)
//CAN初始化
//tsjw:重新同步跳跃时间单元.范围:CAN_SJW_1tq~ CAN_SJW_4tq
//tbs2:时间段2的时间单元. 范围:CAN_BS2_1tq~CAN_BS2_8tq;
//tbs1:时间段1的时间单元. 范…-----CAN1_Mode_Init CAN模式初始化函数:u8 CAN1_Mode_Init(u8 tsjw,u8 tbs2,u8 tbs1,u16 brp,u8 mode)
//CAN初始化
//tsjw:重新同步跳跃时间单元.范围:CAN_SJW_1tq~ CAN_SJW_4tq
//tbs2:时间段2的时间单元. 范围:CAN_BS2_1tq~CAN_BS2_8tq;
//tbs1:时间段1的时间单元. 范围:CAN_BS1_1tq ~CAN_BS1_16tq
//brp :波特率分频器.范围:1~1024; tq(brp)*tpclk1
//波特率Fpclk1/((tbs11tbs211)*brp);
//mode:CAN_Mode_Normal,普通模式;CAN_Mode_LoopBack,回环模式;
//Fpclk1的时钟在初始化的时候设置为42M,如果设置CAN1_Mode_Init(CAN_SJW_1tq,CAN_BS2_6tq,CAN_BS1_7tq,6,CAN_Mode_LoopBack);
//则波特率为:42M/((671)*6)500Kbps
//返回值:0,初始化OK;
// 其他,初始化失败; u8 CAN1_Mode_Init(u8 tsjw,u8 tbs2,u8 tbs1,u16 brp,u8 mode)
{GPIO_InitTypeDef GPIO_InitStructure; CAN_InitTypeDef CAN_InitStructure;CAN_FilterInitTypeDef CAN_FilterInitStructure;
#if CAN1_RX0_INT_ENABLE NVIC_InitTypeDef NVIC_InitStructure;
#endif//使能相关时钟RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);//使能PORTA时钟 /AHB1ENR位 0 GPIOAENIO 端口 A 时钟使能 RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);//使能CAN1时钟 /APB1ENR位 25 CAN1ENCAN 1 时钟使能//初始化GPIOGPIO_InitStructure.GPIO_Pin GPIO_Pin_11| GPIO_Pin_12;GPIO_InitStructure.GPIO_Mode GPIO_Mode_AF;//复用功能GPIO_InitStructure.GPIO_OType GPIO_OType_PP;//推挽输出GPIO_InitStructure.GPIO_Speed GPIO_Speed_100MHz;//100MHzGPIO_InitStructure.GPIO_PuPd GPIO_PuPd_UP;//上拉GPIO_Init(GPIOA, GPIO_InitStructure);//初始化PA11,PA12//引脚复用映射配置GPIO_PinAFConfig(GPIOA,GPIO_PinSource11,GPIO_AF_CAN1); //GPIOA11复用为CAN1GPIO_PinAFConfig(GPIOA,GPIO_PinSource12,GPIO_AF_CAN1); //GPIOA12复用为CAN1//CAN单元设置CAN_InitStructure.CAN_TTCMDISABLE; //非时间触发通信模式 CAN_InitStructure.CAN_ABOMDISABLE; //软件自动离线管理 CAN_InitStructure.CAN_AWUMDISABLE;//睡眠模式通过软件唤醒(清除CAN-MCR的SLEEP位)CAN_InitStructure.CAN_NARTENABLE; //禁止报文自动传送 CAN_InitStructure.CAN_RFLMDISABLE; //报文不锁定,新的覆盖旧的 CAN_InitStructure.CAN_TXFPDISABLE; //优先级由报文标识符决定 CAN_InitStructure.CAN_Mode mode; //模式设置 CAN_InitStructure.CAN_SJWtsjw; //重新同步跳跃宽度(Tsjw)为tsjw1个时间单位 CAN_SJW_1tq~CAN_SJW_4tqCAN_InitStructure.CAN_BS1tbs1; //Tbs1范围CAN_BS1_1tq ~CAN_BS1_16tqCAN_InitStructure.CAN_BS2tbs2;//Tbs2范围CAN_BS2_1tq ~ CAN_BS2_8tqCAN_InitStructure.CAN_Prescalerbrp; //分频系数(Fdiv)为brp1 CAN_Init(CAN1, CAN_InitStructure); // 初始化CAN1 //配置过滤器CAN_FilterInitStructure.CAN_FilterNumber0; //过滤器0CAN_FilterInitStructure.CAN_FilterModeCAN_FilterMode_IdMask; CAN_FilterInitStructure.CAN_FilterScaleCAN_FilterScale_32bit; //32位 CAN_FilterInitStructure.CAN_FilterIdHigh0x0000;32位IDCAN_FilterInitStructure.CAN_FilterIdLow0x0000;CAN_FilterInitStructure.CAN_FilterMaskIdHigh0x0000;//32位MASKCAN_FilterInitStructure.CAN_FilterMaskIdLow0x0000;CAN_FilterInitStructure.CAN_FilterFIFOAssignmentCAN_Filter_FIFO0;//过滤器0关联到FIFO0CAN_FilterInitStructure.CAN_FilterActivationENABLE; //激活过滤器0CAN_FilterInit(CAN_FilterInitStructure);//滤波器初始化#if CAN1_RX0_INT_ENABLECAN_ITConfig(CAN1,CAN_IT_FMP0,ENABLE);//FIFO0消息挂号中断允许. NVIC_InitStructure.NVIC_IRQChannel CAN1_RX0_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority 1; // 主优先级为1NVIC_InitStructure.NVIC_IRQChannelSubPriority 0; // 次优先级为0NVIC_InitStructure.NVIC_IRQChannelCmd ENABLE;NVIC_Init(NVIC_InitStructure);
#endifreturn 0;
}
-----uint8_t CAN_Init /
配置CAN接收滤波器:void CAN_FilterInit /
中断初始化函数:void NVIC_Init can初始化(寄存器操作):uint8_t CAN_Init(CAN_TypeDef* CANx, CAN_InitTypeDef* CAN_InitStruct)
uint8_t CAN_Init(CAN_TypeDef* CANx, CAN_InitTypeDef* CAN_InitStruct)
{uint8_t InitStatus CAN_InitStatus_Failed;uint32_t wait_ack 0x00000000;/* Check the parameters */assert_param(IS_CAN_ALL_PERIPH(CANx));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_TTCM));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_ABOM));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_AWUM));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_NART));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_RFLM));assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct-CAN_TXFP));assert_param(IS_CAN_MODE(CAN_InitStruct-CAN_Mode));assert_param(IS_CAN_SJW(CAN_InitStruct-CAN_SJW));assert_param(IS_CAN_BS1(CAN_InitStruct-CAN_BS1));assert_param(IS_CAN_BS2(CAN_InitStruct-CAN_BS2));assert_param(IS_CAN_PRESCALER(CAN_InitStruct-CAN_Prescaler));/* Exit from sleep mode */CANx-MCR (~(uint32_t)CAN_MCR_SLEEP);//2取反再与,CAN_MCR位1清0,此位由软件清零时将退出睡眠模式/* Request initialisation */CANx-MCR | CAN_MCR_INRQ ;//CAN_MCR位0置1软件通过将此位置 1 来请求 CAN 硬件进入初始化模式/* Wait the acknowledge *///退出初始化模式等待确认while (((CANx-MSR CAN_MSR_INAK) ! CAN_MSR_INAK) (wait_ack ! INAK_TIMEOUT)){//MSR位0 CAN 硬件退出初始化模式以在 CAN 总线上进行同步时此位由硬件清零。(非初始化模式为0)wait_ack; //加到0x0000FFFF退出循环}
//程序在这里由上面的程序到下面,1-未进入初始化模式超时,2-上面的while不成立,已经进入初始化模式/* Check acknowledge */if ((CANx-MSR CAN_MSR_INAK) ! CAN_MSR_INAK)//已经退出初始化模式{InitStatus CAN_InitStatus_Failed;}else {/* Set the time triggered communication mode */if (CAN_InitStruct-CAN_TTCM ENABLE){CANx-MCR | CAN_MCR_TTCM;//MCR位 7 TTCM时间触发通信模式}else{CANx-MCR ~(uint32_t)CAN_MCR_TTCM;}/* Set the automatic bus-off management */if (CAN_InitStruct-CAN_ABOM ENABLE){CANx-MCR | CAN_MCR_ABOM;//MCR位 6 ABOM自动的总线关闭管理}else{CANx-MCR ~(uint32_t)CAN_MCR_ABOM;}/* Set the automatic wake-up mode */if (CAN_InitStruct-CAN_AWUM ENABLE){CANx-MCR | CAN_MCR_AWUM;//位 5 AWUM自动唤醒模式 }else{CANx-MCR ~(uint32_t)CAN_MCR_AWUM;}/* Set the no automatic retransmission */if (CAN_InitStruct-CAN_NART ENABLE){CANx-MCR | CAN_MCR_NART; //位 4 NART禁止自动重发送}else{CANx-MCR ~(uint32_t)CAN_MCR_NART;}/* Set the receive FIFO locked mode */if (CAN_InitStruct-CAN_RFLM ENABLE){CANx-MCR | CAN_MCR_RFLM;//位 3 RFLM接收 FIFO 锁定模式} //1接收 FIFO 上溢后锁定。接收 FIFO 装满后下一条传入消息将被丢弃。else{CANx-MCR ~(uint32_t)CAN_MCR_RFLM;}/* Set the transmit FIFO priority */if (CAN_InitStruct-CAN_TXFP ENABLE){CANx-MCR | CAN_MCR_TXFP;//位 2 TXFP发送 FIFO 优先级;0优先级由消息标识符确定 1优先级由请求顺序时间顺序确定}else{CANx-MCR ~(uint32_t)CAN_MCR_TXFP;}/* Set the bit timing register *///CAN 位时序寄存器 CAN_BTR,/位 30 LBKM环回模式调试/位 25:24 SJW再同步跳转宽度// 位 19:16 TS1时间段 1/位 22:20 TS2时间段 2/位 9:0 BRP波特率预分频器,tq (BRP[9:0]1) x tPCLK(APB的时钟周期)CANx-BTR (uint32_t)((uint32_t)CAN_InitStruct-CAN_Mode 30) | \((uint32_t)CAN_InitStruct-CAN_SJW 24) | \((uint32_t)CAN_InitStruct-CAN_BS1 16) | \((uint32_t)CAN_InitStruct-CAN_BS2 20) | \((uint32_t)CAN_InitStruct-CAN_Prescaler - 1);/* Request leave initialisation */CANx-MCR ~(uint32_t)CAN_MCR_INRQ;//位 0 INRQ软件通过将此位清零来将硬件--切换到正常模式--/* Wait the acknowledge */wait_ack 0;
//MSR位0由硬件置 1用于向软件指示 CAN 硬件此时处于初始化模式。while (((CANx-MSR CAN_MSR_INAK) CAN_MSR_INAK) (wait_ack ! INAK_TIMEOUT)){wait_ack;}//程序到这里:1-处于初始化模式超时,2-上面的while不成立,已经进入正常模式/* ...and check acknowledged */if ((CANx-MSR CAN_MSR_INAK) CAN_MSR_INAK)//CAN 硬件此时处于初始化模式{InitStatus CAN_InitStatus_Failed;}else{InitStatus CAN_InitStatus_Success ;}}/* At this step, return the status of initialization */return InitStatus;
}
配置CAN接收滤波器:void CAN_FilterInit(CAN_FilterInitTypeDef* CAN_FilterInitStruct)
void CAN_FilterInit(CAN_FilterInitTypeDef* CAN_FilterInitStruct)
{uint32_t filter_number_bit_pos 0;//下面的x位,代表0..27筛选器的哪一个/* Check the parameters */assert_param(IS_CAN_FILTER_NUMBER(CAN_FilterInitStruct-CAN_FilterNumber));assert_param(IS_CAN_FILTER_MODE(CAN_FilterInitStruct-CAN_FilterMode));assert_param(IS_CAN_FILTER_SCALE(CAN_FilterInitStruct-CAN_FilterScale));assert_param(IS_CAN_FILTER_FIFO(CAN_FilterInitStruct-CAN_FilterFIFOAssignment));assert_param(IS_FUNCTIONAL_STATE(CAN_FilterInitStruct-CAN_FilterActivation));filter_number_bit_pos ((uint32_t)1) CAN_FilterInitStruct-CAN_FilterNumber;/* Initialisation mode for the filter */CAN1-FMR | FMR_FINIT;//位 0 FINIT置1筛选器进入初始化模式/* Filter Deactivation */CAN1-FA1R ~(uint32_t)filter_number_bit_pos;//软件将x位置 1 可激活筛选器 x,取反是不激活/* Filter Scale */if (CAN_FilterInitStruct-CAN_FilterScale CAN_FilterScale_16bit){/* 16-bit scale for the filter */CAN1-FS1R ~(uint32_t)filter_number_bit_pos;0双 16 位尺度配置/* First 16-bit identifier and First 16-bit mask *///FxR1--标识符和掩码(第1组)或者(列表模式)两个(1和2)标识符/* Or First 16-bit identifier and Second 16-bit identifier */CAN1-sFilterRegister[CAN_FilterInitStruct-CAN_FilterNumber].FR1 ((0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterMaskIdLow) 16) |(0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterIdLow);/* Second 16-bit identifier and Second 16-bit mask *///FxR2--标识符和掩码(第2组)或者(列表模式)两个(3和4)标识符/* Or Third 16-bit identifier and Fourth 16-bit identifier */CAN1-sFilterRegister[CAN_FilterInitStruct-CAN_FilterNumber].FR2 ((0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterMaskIdHigh) 16) |(0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterIdHigh);}if (CAN_FilterInitStruct-CAN_FilterScale CAN_FilterScale_32bit){/* 32-bit scale for the filter *///筛选器尺度寄存器 CAN_FS1R位 27:0 FSCx这些位定义了筛选器13-0的尺度配置。CAN1-FS1R | filter_number_bit_pos; //0双 16 位尺度配置 1单 32 位尺度配置/* 32-bit identifier or First 32-bit identifier *///32位标识符(对应FxR2的32掩码)或第一个32位标识符(列表模式)。--FxR1(手册FiRx)CAN1-sFilterRegister[CAN_FilterInitStruct-CAN_FilterNumber].FR1 ((0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterIdHigh) 16) |(0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterIdLow);/* 32-bit mask or Second 32-bit identifier *///设置32位掩码或第二个32位标识符(列表模式)--FxR2CAN1-sFilterRegister[CAN_FilterInitStruct-CAN_FilterNumber].FR2 ((0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterMaskIdHigh) 16) |(0x0000FFFF (uint32_t)CAN_FilterInitStruct-CAN_FilterMaskIdLow);}/* Filter Mode */if (CAN_FilterInitStruct-CAN_FilterMode CAN_FilterMode_IdMask)//掩码模式{/*Id/Mask mode for the filter*/CAN1-FM1R ~(uint32_t)filter_number_bit_pos;//标识符屏蔽模式}else /* CAN_FilterInitStruct-CAN_FilterMode CAN_FilterMode_IdList *///列表模式{/*Identifier list mode for the filter*/CAN1-FM1R | (uint32_t)filter_number_bit_pos;//寄存器第几位(哪个筛选器组0...27)标识符列表模式}/* Filter FIFO assignment *///过滤器FIFO先进先出分配的设置if (CAN_FilterInitStruct-CAN_FilterFIFOAssignment CAN_Filter_FIFO0)//FIFO0{/* FIFO 0 assignation for the filter */CAN1-FFA1R ~(uint32_t)filter_number_bit_pos;//CAN筛选器FIFO分配寄存器(CAN_FFA1R)0:筛选器分配到FIFO0/1:筛选器分配到 FIFO1}if (CAN_FilterInitStruct-CAN_FilterFIFOAssignment CAN_Filter_FIFO1)//FIFO1{/* FIFO 1 assignation for the filter */CAN1-FFA1R | (uint32_t)filter_number_bit_pos;}/* Filter activation *///过滤器激活的设置if (CAN_FilterInitStruct-CAN_FilterActivation ENABLE){CAN1-FA1R | filter_number_bit_pos;//筛选器 x 激活}/* Leave the initialisation mode for the filter */CAN1-FMR ~FMR_FINIT;//位 0 FINIT筛选器初始化模式,取反就是工作模式
}中断初始化函数:void NVIC_Init(NVIC_InitTypeDef* NVIC_InitStruct)
/*** brief Initializes the NVIC peripheral according to the specified* parameters in the NVIC_InitStruct.* note To configure interrupts priority correctly, the NVIC_PriorityGroupConfig()* function should be called before. * param NVIC_InitStruct: pointer to a NVIC_InitTypeDef structure that contains* the configuration information for the specified NVIC peripheral.* retval None*/
void NVIC_Init(NVIC_InitTypeDef* NVIC_InitStruct)
{uint8_t tmppriority 0x00, tmppre 0x00, tmpsub 0x0F;/* Check the parameters */assert_param(IS_FUNCTIONAL_STATE(NVIC_InitStruct-NVIC_IRQChannelCmd));//中断使能参数检查assert_param(IS_NVIC_PREEMPTION_PRIORITY(NVIC_InitStruct-NVIC_IRQChannelPreemptionPriority));//抢占优先级 assert_param(IS_NVIC_SUB_PRIORITY(NVIC_InitStruct-NVIC_IRQChannelSubPriority));//相应优先级if (NVIC_InitStruct-NVIC_IRQChannelCmd ! DISABLE)//如中断使能{/* Compute the Corresponding IRQ Priority -------*/ //寄存器AIRCR(内核指南手册)位10:8,优先级分组 tmppriority (0x700 - ((SCB-AIRCR) (uint32_t)0x700)) 0x08;//7减AIRCR[10:8]得中断组号tmppre (0x4 - tmppriority);//4减中断组号得响应优先级所占的位数(总位数为4,IP[7:4])tmpsub tmpsub tmppriority;//0x0F左移中断组号得响应优先级最大值tmppriority NVIC_InitStruct-NVIC_IRQChannelPreemptionPriority tmppre;//抢占优先级左移响应优先级位数(相对响应优先级的位置)tmppriority | (uint8_t)(NVIC_InitStruct-NVIC_IRQChannelSubPriority tmpsub);//响应优先级和抢占优先级的4位组合//假设为分组2(对应寄存器位101,AIRCR寄存器值设0x0F5A0500),抢占1--0100,组合响应3---0111//AIRCR[31:16]任何对该寄存器的写操作都必须同时把 0x05FA 写入此段tmppriority tmppriority 0x04;//把优先级值写入NVIC_IP寄存器[7:4]//NVIC_IRQChannel中断源对应中断向量表,例如can1中断,CAN1_RX0_IRQn 20 , NVIC-IP[20]0111NVIC-IP[NVIC_InitStruct-NVIC_IRQChannel] tmppriority;/* Enable the Selected IRQ Channels --------------------------------------*/NVIC-ISER[NVIC_InitStruct-NVIC_IRQChannel 0x05] //中断源使能,ISERx是按32位偏移所以左移5,代表是第几个寄存器(uint32_t)0x01 (NVIC_InitStruct-NVIC_IRQChannel (uint8_t)0x1F);//与0x1F相当于除以32取余,代表在第几位} //假设中断向量是20,NVIC-ISER[0]0x010x14//假设中断向量是(USART1_IRQn )37,NVIC-ISER[1]0x010x05else//假设中断向量是(I2C1_ER_IRQn)32,NVIC-ISER[1]0x010x0{/* Disable the Selected IRQ Channels -------------------------------------*/NVIC-ICER[NVIC_InitStruct-NVIC_IRQChannel 0x05] //中断源失能(uint32_t)0x01 (NVIC_InitStruct-NVIC_IRQChannel (uint8_t)0x1F);}
} -----can发送底层函数:uint8_t CAN_Transmit
can接收底层函数:void CAN_Receive
can发送函数:u8 CAN1_Send_Msg(u8* msg,u8 len)和接收函数:u8 CAN1_Receive_Msg(u8 *buf)
//can发送一组数据(固定格式:ID为0X12,标准帧,数据帧)
//len:数据长度(最大为8)
//msg:数据指针,最大为8个字节.
//返回值:0,成功;
// 其他,失败;
u8 CAN1_Send_Msg(u8* msg,u8 len)
{ u8 mbox;u16 i0;CanTxMsg TxMessage;TxMessage.StdId0x12; // 标准标识符为0TxMessage.ExtId0x12; // 设置扩展标示符29位TxMessage.IDE0; // 使用扩展标识符,/为0是标准帧,4(二进制100,这样就无需再移位直接对应了寄存器的位)扩展帧TxMessage.RTR0; // 消息类型为数据帧/标准数据帧通常包含8个数据位,0数据帧,2(10)遥控帧TxMessage.DLClen; // 数据字段有多少个字节for(i0;ilen;i) //这个循环用于复制数据到TxMessage的数据字段TxMessage.Data[i]msg[i]; mbox CAN_Transmit(CAN1, TxMessage); // 通过CAN1接口发送TxMessage,返回值是三个邮箱0或1或2i0;while((CAN_TransmitStatus(CAN1, mbox)CAN_TxStatus_Failed)(i0XFFF))i; //邮箱的发送消息状态失败等待超时if(i0XFFF)return 1;return 0; //返回0代表发送成功 }
//can口接收数据查询
//buf:数据缓存区;
//返回值:0,无数据被收到;
// 其他,接收的数据长度;
u8 CAN1_Receive_Msg(u8 *buf)
{ u32 i;CanRxMsg RxMessage;if( CAN_MessagePending(CAN1,CAN_FIFO0)0)return 0; //CAN_FIFO0挂起的消息数量为0,没有待处理的消息,函数立即返回0,忽略后面的代码CAN_Receive(CAN1, CAN_FIFO0, RxMessage);//能执行到这里,就代表有消息,则从FIFO0中接收该消息 for(i0;iRxMessage.DLC;i)buf[i]RxMessage.Data[i]; return RxMessage.DLC; //最后返回接收的数据长度(其数值是通过CAN_Receive函数的调用被填充到RxMessage结构体中的)
}can发送底层函数:uint8_t CAN_Transmit(CAN_TypeDef* CANx, CanTxMsg* TxMessage)
uint8_t CAN_Transmit(CAN_TypeDef* CANx, CanTxMsg* TxMessage)
{ uint8_t transmit_mailbox 0;/* Check the parameters */assert_param(IS_CAN_ALL_PERIPH(CANx));assert_param(IS_CAN_IDTYPE(TxMessage-IDE));assert_param(IS_CAN_RTR(TxMessage-RTR));assert_param(IS_CAN_DLC(TxMessage-DLC));/* Select one empty transmit mailbox *///选择一个空邮箱if ((CANx-TSRCAN_TSR_TME0) CAN_TSR_TME0)//TSR位 26,当邮箱 0 没有挂起的发送请求时此位由硬件置 1。{transmit_mailbox 0;}else if ((CANx-TSRCAN_TSR_TME1) CAN_TSR_TME1)//TSR位 27,邮箱 1{transmit_mailbox 1;}else if ((CANx-TSRCAN_TSR_TME2) CAN_TSR_TME2)//TSR位 28,邮箱 2{transmit_mailbox 2;}else{transmit_mailbox CAN_TxStatus_NoMailBox;//4}if (transmit_mailbox ! CAN_TxStatus_NoMailBox)//有邮箱被选中{/* Set up the Id */CANx-sTxMailBox[transmit_mailbox].TIR TMIDxR_TXRQ;//位 0 TXRQ发送邮箱请求/寄存器保留位0,忽略其他位if (TxMessage-IDE CAN_Id_Standard){assert_param(IS_CAN_STDID(TxMessage-StdId)); //位 31:21 STID[10:0]/EXID[28:18]标准标识符或扩展标识符 CANx-sTxMailBox[transmit_mailbox].TIR | ((TxMessage-StdId 21) | \TxMessage-RTR);}else{assert_param(IS_CAN_EXTID(TxMessage-ExtId));CANx-sTxMailBox[transmit_mailbox].TIR | ((TxMessage-ExtId 3) | \TxMessage-IDE | \TxMessage-RTR);}/* Set up the DLC */TxMessage-DLC (uint8_t)0x0000000F;CANx-sTxMailBox[transmit_mailbox].TDTR (uint32_t)0xFFFFFFF0;//低4位清0,其他位不变CANx-sTxMailBox[transmit_mailbox].TDTR | TxMessage-DLC;/* Set up the data field *///最多8个(字节)数据占64个位,两个寄存器CANx-sTxMailBox[transmit_mailbox].TDLR (((uint32_t)TxMessage-Data[3] 24) | ((uint32_t)TxMessage-Data[2] 16) |((uint32_t)TxMessage-Data[1] 8) | ((uint32_t)TxMessage-Data[0]));CANx-sTxMailBox[transmit_mailbox].TDHR (((uint32_t)TxMessage-Data[7] 24) | ((uint32_t)TxMessage-Data[6] 16) |((uint32_t)TxMessage-Data[5] 8) |((uint32_t)TxMessage-Data[4]));/* Request transmission */CANx-sTxMailBox[transmit_mailbox].TIR | TMIDxR_TXRQ;//TIxR寄存器位0置1用于请求发送相应邮箱的内容}return transmit_mailbox;
}can接收底层函数:void CAN_Receive(CAN_TypeDef* CANx, uint8_t FIFONumber, CanRxMsg* RxMessage)
void CAN_Receive(CAN_TypeDef* CANx, uint8_t FIFONumber, CanRxMsg* RxMessage)//
{/* Check the parameters */assert_param(IS_CAN_ALL_PERIPH(CANx));assert_param(IS_CAN_FIFO(FIFONumber));/* Get the Id */RxMessage-IDE (uint8_t)0x04 CANx-sFIFOMailBox[FIFONumber].RIR;//形参RxMessage赋值,如果是0,ID标准帧if (RxMessage-IDE CAN_Id_Standard){RxMessage-StdId (uint32_t)0x000007FF (CANx-sFIFOMailBox[FIFONumber].RIR 21);} //标准帧寄存器值右移21,与7FF是因为标准帧数据只有11位else{RxMessage-ExtId (uint32_t)0x1FFFFFFF (CANx-sFIFOMailBox[FIFONumber].RIR 3);//扩展帧右移3}RxMessage-RTR (uint8_t)0x02 CANx-sFIFOMailBox[FIFONumber].RIR;//接收的是数据帧还是遥控帧/* Get the DLC */RxMessage-DLC (uint8_t)0x0F CANx-sFIFOMailBox[FIFONumber].RDTR;//接收的数据帧长度/* Get the FMI *///获取筛选器编号/邮箱中存储的消息需要经过该筛选器RxMessage-FMI (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDTR 8);/* Get the data field */RxMessage-Data[0] (uint8_t)0xFF CANx-sFIFOMailBox[FIFONumber].RDLR;RxMessage-Data[1] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDLR 8);RxMessage-Data[2] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDLR 16);RxMessage-Data[3] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDLR 24);RxMessage-Data[4] (uint8_t)0xFF CANx-sFIFOMailBox[FIFONumber].RDHR;RxMessage-Data[5] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDHR 8);RxMessage-Data[6] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDHR 16);RxMessage-Data[7] (uint8_t)0xFF (CANx-sFIFOMailBox[FIFONumber].RDHR 24);/* Release the FIFO *//* Release FIFO0 *///释放该邮箱if (FIFONumber CAN_FIFO0){CANx-RF0R | CAN_RF0R_RFOM0;//位 5 RFOM0释放 FIFO 0 输出邮箱,释放后此位由硬件清零。}/* Release FIFO1 */else /* FIFONumber CAN_FIFO1 */{CANx-RF1R | CAN_RF1R_RFOM1;}
}
-----中断向量关联图:
