广州网站建设 易点c 后端开发需要哪些技能？
摘要：广州网站建设 易点,c++后端开发需要学什么,网站多网合一,柳州专业网站建设加盟最近公司做一个项目，需要3路can通道，但是stm32看了很久，最多也
广州网站建设 易点,c++后端开发需要学什么,网站多网合一,柳州专业网站建设加盟最近公司做一个项目#xff0c;需要3路can通道#xff0c;但是stm32看了很久#xff0c;最多也就只有2个can#xff0c;所以找到了一款MCP2515芯片#xff0c;可以用spi驱动can。 已经实现了can的发送和接收#xff0c;接收采用的是外部中断接收的方式。和单片机本身带的…最近公司做一个项目需要3路can通道但是stm32看了很久最多也就只有2个can所以找到了一款MCP2515芯片可以用spi驱动can。 已经实现了can的发送和接收接收采用的是外部中断接收的方式。和单片机本身带的can功能一样。 还有就是要注意的是CAN的接收是通过外部中断引脚下拉来确定接收缓冲器接收到数据可以通过设置接收屏蔽和滤波。 spi的初始化就不介绍 直接放出MCP2515的关键代码 首先是MCP2515的头文件 主要是一些宏定义和API
#ifndef MCP2515_H_
#define MCP2515_H_
#include stm32f10x.h#define USE_INT_STAT 1 // use INT pin indicate recived data//MCP2515 RX/TX buffers selection
#define MCP2515_RX_BUF_0 0
#define MCP2515_RX_BUF_1 1
#define MCP2515_TX_BUF_0 0
#define MCP2515_TX_BUF_1 1
#define MCP2515_TX_BUF_2 2//MCP2515 SPI instructions
#define MCP2515_RESET 0xC0
#define MCP2515_READ 0x03
#define MCP2515_READ_BUF_RXB0SIDH 0x90 //read data from begin address of Standard ID (MSB) of RX buffer 0
#define MCP2515_READ_BUF_RXB0D0 0x92 //read data from begin address of data byte 0 of RX buffer 0
#define MCP2515_READ_BUF_RXB1SIDH 0x94 //...RX buffer 1
#define MCP2515_READ_BUF_RXB1D0 0x96 //...RX buffer 1
#define MCP2515_WRITE 0x02
#define MCP2515_LOAD_BUF_TXB0SIDH 0x40 //load data from begin address of Standard ID (MSB) of TX buffer 0
#define MCP2515_LOAD_BUF_TXB0D0 0X41 //load data from begin address of data byte 0 of TX buffer 0
#define MCP2515_LOAD_BUF_TXB1SIDH 0x42 //...TX buffer 1
#define MCP2515_LOAD_BUF_TXB1D0 0X43 //...TX buffer 1
#define MCP2515_LOAD_BUF_TXB2SIDH 0x44 //...TX buffer 2
#define MCP2515_LOAD_BUF_TXB2D0 0X45 //...TX buffer 2
#define MCP2515_RTS_TXB0 0x81 //activate the RTS of TX buffer 0.
#define MCP2515_RTS_TXB1 0x82 //...TX buffer 1.
#define MCP2515_RTS_TXB2 0x84 //...TX buffer 2.
#define MCP2515_RTS_ALL 0x87 //...TX buffer 0, 1 and 2.
#define MCP2515_READ_RXTX_STATUS 0xA0
#define MCP2515_RX_STATUS 0xB0
#define MCP2515_BIT_MODIFY 0x05//MCP2515 control settings register address.
//All can be used with the Bit Modify command, except the CANSTAT register.
#define MCP2515_BFPCTRL 0x0C //RXnBF pin control/status
#define MCP2515_TXRTSCTRL 0x0D //TXnRTS pin control/status
#define MCP2515_CANSTAT 0x0E //CAN status. any addr of MSB will give the same info???
#define MCP2515_CANCTRL 0x0F //CAN control status. any addr of MSB will give the same info???
#define MCP2515_TEC 0x1C //Transmit Error Counter
#define MCP2515_REC 0x1D //Receive Error Counter
#define MCP2515_CNF3 0x28 //Phase segment 2
#define MCP2515_CNF2 0x29 //Propagation segment Phase segment 1 n sample setting
#define MCP2515_CNF1 0x2A //Baud rate prescaler Sync Jump Width
#define MCP2515_CANINTE 0x2B //CAN interrupt enable
#define MCP2515_CANINTF 0x2C //Interrupt flag
#define MCP2515_EFLG 0x2D //Error flag
#define MCP2515_TXB0CTRL 0x30 //TX buffer 0 control
#define MCP2515_TXB1CTRL 0x40 //TX buffer 1 control
#define MCP2515_TXB2CTRL 0x50 //TX buffer 2 control
#define MCP2515_RXB0CTRL 0x60 //RX buffer 0 control
#define MCP2515_RXB1CTRL 0x70 //RX buffer 1 control//MCP2515 relate to CAN settings/status register address.
//Only the most used are listed below. please see the datasheet MCP2515.pdf p61 for complete info.
#define MCP2515_RXF0SIDH 0x00 //RX standard ID (High bits) filter 0
#define MCP2515_RXF0SIDL 0x01 //RX standard ID (Low bits) filter 0
#define MCP2515_RXF0EID8 0x02 //RX Extended ID (High bits) filter 0 -can be reached by bust read/write Standard ID then Ext. ID
#define MCP2515_RXF0EID0 0x03 //RX Extended ID (Low bits) filter 0
#define MCP2515_RXF1SIDH 0x04 //RX standard ID (High bits) filter 1
#define MCP2515_RXF1SIDL 0x05 //RX standard ID (Low bits) filter 1
#define MCP2515_RXF1EID8 0x06 //RX Extended ID (High bits) filter 1
#define MCP2515_RXF1EID0 0x07 //RX Extended ID (Low bits) filter 1
#define MCP2515_RXF2SIDH 0x08 //RX standard ID (High bits) filter 2
#define MCP2515_RXF2SIDL 0x09 //RX standard ID (Low bits) filter 2
#define MCP2515_RXF2EID8 0x0A //RX Extended ID (High bits) filter 2
#define MCP2515_RXF2EID0 0x0B //RX Extended ID (Low bits) filter 2
#define MCP2515_RXF3SIDH 0x10 //RX standard ID (High bits) filter 3
#define MCP2515_RXF3SIDL 0x11 //RX standard ID (Low bits) filter 3
#define MCP2515_RXF3EID8 0x12 //RX Extended ID (High bits) filter 3
#define MCP2515_RXF3EID0 0x13 //RX Extended ID (Low bits) filter 3
#define MCP2515_RXF4SIDH 0x14 //RX standard ID (High bits) filter 4
#define MCP2515_RXF4SIDL 0x15 //RX standard ID (Low bits) filter 4
#define MCP2515_RXF4EID8 0x16 //RX Extended ID (High bits) filter 4
#define MCP2515_RXF4EID0 0x17 //RX Extended ID (Low bits) filter 4
#define MCP2515_RXF5SIDH 0x18 //RX standard ID (High bits) filter 5
#define MCP2515_RXF5SIDL 0x19 //RX standard ID (Low bits) filter 5
#define MCP2515_RXF5EID8 0x1A //RX Extended ID (High bits) filter 5
#define MCP2515_RXF5EID0 0x1B //RX Extended ID (Low bits) filter 5
#define MCP2515_RXM0SIDH 0x20 //RX standard ID (High bits) mask filter 0
#define MCP2515_RXM0SIDL 0x21 //RX standard ID (Low bits) mask filter 0
#define MCP2515_RXM0EID8 0x22 //RX Extended ID (High bits) mask filter 0
#define MCP2515_RXM0EID0 0x23 //RX Extended ID (Low bits) mask filter 0
#define MCP2515_RXM1SIDH 0x24 //RX standard ID (High bits) mask filter 1
#define MCP2515_RXM1SIDL 0x25 //RX standard ID (Low bits) mask filter 1
#define MCP2515_RXM1EID8 0x26 //RX Extended ID (High bits) mask filter 1
#define MCP2515_RXM1EID0 0x27 //RX Extended ID (Low bits) mask filter 1
#define MCP2515_RXB0SIDH 0x61 //RX buffer 0 standard ID (High bits)
#define MCP2515_RXB0SIDL 0x62 //RX buffer 0 standard ID (Low bits)
#define MCP2515_RXB0EID8 0x63 //RX buffer 0 Extended ID (High bits) -can be reached by bust read/write Standard ID then Ext. ID
#define MCP2515_RXB0EID0 0x64 //RX buffer 0 Extended ID (Low bits)
#define MCP2515_RXB0DLC 0x65 //RX buffer 0 DLC -can be reached by bust read/write Standard ID, Ext. ID then DLC
#define MCP2515_RXB0D0 0x66 //RX buffer 0 data byte0
#define MCP2515_RXB1SIDH 0x71 //RX buffer 1 standard ID (High bits)
#define MCP2515_RXB1SIDL 0x72 //RX buffer 1 standard ID (Low bits)
#define MCP2515_RXB1EID8 0x73 //RX buffer 1 Extended ID (High bits)
#define MCP2515_RXB1EID0 0x74 //RX buffer 1 Extended ID (Low bits)
#define MCP2515_RXB1DLC 0x75 //RX buffer 1 DLC
#define MCP2515_RXB1D0 0x76 //RX buffer 1 data byte0#define MCP2515_TXB0SIDH 0x31 //TX buffer 0 standard ID (High bits)
#define MCP2515_TXB0SIDL 0x32 //TX buffer 0 standard ID (Low bits)
#define MCP2515_TXB0EID8 0x33 //TX buffer 0 Extended ID (High bits) -can be reached by bust read/write Standard ID then Ext. ID
#define MCP2515_TXB0EID0 0x34 //TX buffer 0 Extended ID (Low bits)
#define MCP2515_TXB0DLC 0x35 //TX buffer 0 DLC -can be reached by bust read/write Standard ID, Ext. ID then DLC
#define MCP2515_TXB0D0 0x36 //TX buffer 0 data byte0
#define MCP2515_TXB1SIDH 0x41 //TX buffer 1 standard ID (High bits)
#define MCP2515_TXB1SIDL 0x42 //TX buffer 1 standard ID (Low bits)
#define MCP2515_TXB1EID8 0x43 //TX buffer 1 Extended ID (High bits)
#define MCP2515_TXB1EID0 0x44 //TX buffer 1 Extended ID (Low bits)
#define MCP2515_TXB1DLC 0x45 //TX buffer 1 DLC
#define MCP2515_TXB1D0 0x46 //TX buffer 1 data byte0
#define MCP2515_TXB2SIDH 0x51 //TX buffer 2 standard ID (High bits)
#define MCP2515_TXB2SIDL 0x52 //TX buffer 2 standard ID (Low bits)
#define MCP2515_TXB2EID8 0x53 //TX buffer 2 Extended ID (High bits)
#define MCP2515_TXB2EID0 0x54 //TX buffer 2 Extended ID (Low bits)
#define MCP2515_TXB2DLC 0x55 //TX buffer 2 DLC
#define MCP2515_TXB2D0 0x56 //TX buffer 2 data byte0//MCP2515 limit values
#define MCP2515_MIN_TQ 0x07 //7 Minimum TQ in 1 bit of CAN bus time
#define MCP2515_MAX_TQ 0x19 //25 Maximum TQ in 1 bit of CAN bus time
#define MCP2515_MIN_BRP 0x00 //0 Minimum baud rate prescaler clock
#define MCP2515_MAX_BRP 0x3F //63 Maximum baud rate prescaler clock
#define MCP2515_MAX_SJW 0x03 //4 Maximum Synchronization Jump Width. 4-1 3 actually
#define MCP2515_MAX_BYTE_CANFRM 0x08//8 Maximun bytes in a CAN frame//MCP2515 register values: CANCTRL register
#define MCP2515_MODE_NORMAL 0x00
#define MCP2515_MODE_SLEEP 0x20
#define MCP2515_MODE_LOOPBACK 0x40
#define MCP2515_MODE_LISTENONLY 0x60
#define MCP2515_MODE_CONFIG 0x80
#define MCP2515_ABORT_TX 0x10
#define MCP2515_MODE_MASK 0xE0
#define MCP2515_MODE_ONESHOT 0x08
#define MCP2515_CLKOUT_ENABLE 0x04
#define MCP2515_CLKOUT_PS1 0x00 //Set CLK out prescaler to 1. Note: not the same as the CAN CLK prescaler.
#define MCP2515_CLKOUT_PS2 0x01 //... to 2
#define MCP2515_CLKOUT_PS4 0x02 //... to 4
#define MCP2515_CLKOUT_PS8 0x03 //... to 8//MCP2515 CAN Status Register bits (CANSTAT 0xXE, ICOD)
#define MCP2515_CANSTAT_NO_INT 0x00
#define MCP2515_CANSTAT_ERR_INT 0x02
#define MCP2515_CANSTAT_WAK_INT 0x04 //Wake-up Interrupt
#define MCP2515_CANSTAT_TXB0_INT 0x06
#define MCP2515_CANSTAT_TXB1_INT 0x08
#define MCP2515_CANSTAT_TXB2_INT 0x0A
#define MCP2515_CANSTAT_RXB0_INT 0x0C
#define MCP2515_CANSTAT_RXB1_INT 0x0E//MCP2515 CAN Interrupt Flag Define
#define MCP2515_CANINTF_MERRF 0x80
#define MCP2515_CANINTF_WAKIF 0x40
#define MCP2515_CANINTF_ERRIF 0x20
#define MCP2515_CANINTF_TX2IF 0x10
#define MCP2515_CANINTF_TX1IF 0x08
#define MCP2515_CANINTF_TX0IF 0x04
#define MCP2515_CANINTF_RX1IF 0x02
#define MCP2515_CANINTF_RX0IF 0x01#define MCP2515_CANINT_MERR 0x80
#define MCP2515_CANINT_WAKI 0x40
#define MCP2515_CANINT_ERRI 0x20
#define MCP2515_CANINT_TX2I 0x10
#define MCP2515_CANINT_TX1I 0x08
#define MCP2515_CANINT_TX0I 0x04
#define MCP2515_CANINT_RX1I 0x02
#define MCP2515_CANINT_RX0I 0x01#define MCP2515_CAN_Standard (0) /*! Standard Id */
#define MCP2515_CAN_Extended (8) /*! Extended Id */
/** * brief MCP2515_CAN Tx message structure definition */typedef struct
{uint32_t StdId; /*! Specifies the standard identifier.This parameter can be a value between 0 to 0x7FF. */uint32_t ExtId; /*! Specifies the extended identifier.This parameter can be a value between 0 to 0x1FFFFFFF. */unsigned char IDE; /*! Specifies the type of identifier for the message that will be transmitted. This parameter can be a value of ref CAN_identifier_type */unsigned char RTR; /*! Specifies the type of frame for the message that will be transmitted. This parameter can be a value of ref CAN_remote_transmission_request */unsigned char DLC; /*! Specifies the length of the frame that will be transmitted. This parameter can be a value between 0 to 8 */unsigned char Data[8]; /*! Contains the data to be transmitted. It ranges from 0 to 0xFF. */
}MCP2515_CanTxMsg;/** * brief MCP2515_CAN Rx message structure definition */typedef struct
{uint32_t StdId; /*! Specifies the standard identifier.This parameter can be a value between 0 to 0x7FF. */uint32_t ExtId; /*! Specifies the extended identifier.This parameter can be a value between 0 to 0x1FFFFFFF. */unsigned char IDE; /*! Specifies the type of identifier for the message that will be received. This parameter can be a value of ref CAN_identifier_type */unsigned char RTR; /*! Specifies the type of frame for the received message.This parameter can be a value of ref CAN_remote_transmission_request */unsigned char DLC; /*! Specifies the length of the frame that will be received.This parameter can be a value between 0 to 8 */unsigned char Data[8]; /*! Contains the data to be received. It ranges from 0 to 0xFF. */unsigned char FMI; /*! Specifies the index of the filter the message stored in the mailbox passes through. This parameter can be a value between 0 to 0xFF */
}MCP2515_CanRxMsg;extern MCP2515_CanRxMsg MCP2515_Rxmsg;
extern MCP2515_CanTxMsg MCP2515_Txmsg;/*KEY API*/
void MCP2515_CAN_Init(unsigned char brp,unsigned char ps1,unsigned char ps2);
unsigned char MCP2515_CAN_ReceiveData(MCP2515_CanRxMsg * rxmsg);
void MCP2515_CAN_SendData(MCP2515_CanTxMsg *txmsg);
void CANINT_GPIO_Init(void);/*General API*/
void MCP2515_Reset(void);
unsigned char MCP2515_ReadByte(unsigned char addr);
void MCP2515_WriteByte(unsigned char addr,unsigned char data);
void MCP2515_BitModify(unsigned char Addr, unsigned char MASK, unsigned char data);
uint8_t MCP2515_Get_ReadStatus(void);
uint8_t MCP2515_Get_RxStatus(void);
void MCP2515_RTS(unsigned char TxBn);/*Set MCP2515*/
void MCP2515_SetCNF1(unsigned char data);
void MCP2515_SetCNF2(unsigned char data);
void MCP2515_SetCNF3(unsigned char data);
void MCP2515_SetMode(unsigned char data);
unsigned char MCP2515_GetCanStatus(void);/*TX API*/
void MCP2515_SetTXID(unsigned char TxBnID,MCP2515_CanTxMsg *txmsg);
void MCP2515_SetTXDLC(unsigned char TxBnDLC,MCP2515_CanTxMsg *txmsg);
void MCP2515_SetTXDATA(unsigned char TxBnDm,MCP2515_CanTxMsg *txmsg);/*RX API*/#endif /*MCP2515_H_*/
接下来就是MCP2515的源文件代码 和头文件是对应的
#include mcp2515.h
#include spi.h
#include System/Utils.h
#include GPIO/GPIO.h
#include stdio.hMCP2515_CanRxMsg MCP2515_Rxmsg;
MCP2515_CanTxMsg MCP2515_Txmsg;void EXTI9_5_IRQHandler(void)
{if(!GPIO_ReadInputDataBit(GPIOD,GPIO_Pin_9)){/*can中断*/MCP2515_CAN_ReceiveData(MCP2515_Rxmsg);}EXTI_ClearITPendingBit(EXTI_Line9); //清除LINE9上的中断标志位
}
void CANINT_GPIO_Init(void)
{GPIO_InitTypeDef GPIO_InitStructure;EXTI_InitTypeDef EXTI_InitStructure;NVIC_InitTypeDef NVIC_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD|RCC_APB2Periph_AFIO,ENABLE);GPIO_InitStructure.GPIO_Pin GPIO_Pin_9;GPIO_InitStructure.GPIO_Mode GPIO_Mode_IPU; //设置成上拉输入GPIO_Init(GPIOD, GPIO_InitStructure);//中断线以及中断初始化配置 下降沿触发GPIO_EXTILineConfig(GPIO_PortSourceGPIOD,GPIO_PinSource9); EXTI_InitStructure.EXTI_LineEXTI_Line9;EXTI_InitStructure.EXTI_Mode EXTI_Mode_Interrupt; EXTI_InitStructure.EXTI_Trigger EXTI_Trigger_Falling;EXTI_InitStructure.EXTI_LineCmd ENABLE;EXTI_Init(EXTI_InitStructure); //根据EXTI_InitStruct中指定的参数初始化外设EXTI寄存器NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);NVIC_InitStructure.NVIC_IRQChannel EXTI9_5_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority 0x01; NVIC_InitStructure.NVIC_IRQChannelSubPriority 0x01;NVIC_InitStructure.NVIC_IRQChannelCmd ENABLE;NVIC_Init(NVIC_InitStructure); }/********* * brief MCP2515_CAN_Init* param brp:0~63* param ps1:0~7* param ps2:1~7* BaudrateFosc/( 2 (ps11) (ps21) ) * 2*(1brp) )* eg:brp1 ps13 ps21Baudrate8Mhz/(2(31)(11))*2*(11) 250Khz* eg:brp0 ps13 ps21Baudrate8Mhz/(2(11)(11))*2*(11) 250Khz* retval none*/
void MCP2515_CAN_Init(unsigned char brp,unsigned char ps1,unsigned char ps2)
{这个是CAN初始化的代码 主要是配置CAN的波特率 模式 通道等具体代码可以小窗找我
}/********* * brief Receive n bytes from MCP2515 RXB0* param rxmsg:RxDataStruct* retval Data:return the effectively data from RXB0*/
unsigned char MCP2515_CAN_ReceiveData(MCP2515_CanRxMsg * rxmsg)
{这个是CAN的接收函数 可以在中断中来读取这个API 得到接收的can数据具体代码可以小窗找我}
/********* * brief Send n bytes to MCP2515 txb0* param txmsg: data to be sent * retval None*/
void MCP2515_CAN_SendData(MCP2515_CanTxMsg *txmsg)
{这个是CAN的发送函数 代入CAN的结构体参数就可以具体代码可以小窗找我
}//功能复位MCP2515
void MCP2515_Reset(void)
{MC2515_CS(0);SPI_MCP2515_Write_Read(MCP2515_RESET);MC2515_CS(1);
}
//功能读MCP2515的数据
//入口参数Addr:寄存器地址
//返回值寄存器地址中的数据
unsigned char MCP2515_ReadByte(unsigned char addr)
{unsigned char ReadData;MC2515_CS(0);SPI_MCP2515_Write_Read(MCP2515_READ);SPI_MCP2515_Write_Read(addr);ReadDataSPI_MCP2515_Write_Read(0xff);MC2515_CS(1);return ReadData;
}
//功能读MCP2515的寄存器
//入口参数Addr:寄存器地址 data:数据字节
void MCP2515_WriteByte(unsigned char addr,unsigned char data)
{MC2515_CS(0);SPI_MCP2515_Write_Read(MCP2515_WRITE);SPI_MCP2515_Write_Read(addr);SPI_MCP2515_Write_Read(data);MC2515_CS(1);
}
//功能只修改寄存器中的某些位
//入口参数Addr:寄存器地址 MASK屏蔽字 data:数据字节
void MCP2515_BitModify(unsigned char Addr, unsigned char MASK, unsigned char data)
{MC2515_CS(0);SPI_MCP2515_Write_Read(MCP2515_BIT_MODIFY);SPI_MCP2515_Write_Read(Addr);SPI_MCP2515_Write_Read(MASK);SPI_MCP2515_Write_Read(data);MC2515_CS(1);
}
//功能获取读状态指令中的数据
//返回值读状态指令中的数据
uint8_t MCP2515_Get_ReadStatus(void)
{unsigned char ReadData;MC2515_CS(0); ReadDataSPI_MCP2515_Write_Read(MCP2515_READ_RXTX_STATUS);MC2515_CS(1);return ReadData;
}
//功能获取读状态指令中的数据
//返回值读状态指令中的数据
uint8_t MCP2515_Get_RxStatus(void)
{unsigned char ReadData;MC2515_CS(0); ReadDataSPI_MCP2515_Write_Read(MCP2515_RX_STATUS);MC2515_CS(1);return ReadData;
}
//功能请求发送功能
//入口参数TxBn 发送缓冲器序号
//MCP2515_RTS_TXB0/MCP2515_RTS_TXB1/MCP2515_RTS_TXB2/MCP2515_RTS_ALL
void MCP2515_RTS(unsigned char TxBn)
{MC2515_CS(0); SPI_MCP2515_Write_Read(TxBn);MC2515_CS(1);
}
/*
bit 7-6 SJW同步跳转宽度位 1:011 长度 4 x TQ10 长度 3 x TQ01 长度 2 x TQ00 长度 1 x TQ
bit 5-0 BRP波特率预分频比位 5:0TQ 2 x (BRP 1)/FOSC
*/
void MCP2515_SetCNF1(unsigned char data)
{MCP2515_WriteByte(MCP2515_CNF1,data);
}/*
bit 7 BTLMODE相位缓冲段 PS2 位时间长度位1 PS2 时间长度由 CNF3 的 PHSEG22:PHSEG20 位决定0 PS2 时间长度为 PS1 和 IPT 2 TQ两者的较大值
bit 6 SAM采样点配置位1 在采样点对总线进行三次采样0 在采样点对总线进行一次采样
bit 5-3 PHSEG1相位缓冲段 PS1 位时间长度位 2:0(PHSEG1 1) x TQ
bit 2-0 PRSEG传播段长度位 2:0(PRSEG 1) x TQ
*/
void MCP2515_SetCNF2(unsigned char data)
{MCP2515_WriteByte(MCP2515_CNF2,data);
}/*
bit 7 SOF起始帧信号位如果 CANCTRL.CLKEN 11 CLKOUT 引脚使能为 SOF 信号0 CLKOUT 引脚使能为时间输出功能如果 CANCTRL.CLKEN 0该位为任意状态 .
bit 6 WAKFIL唤醒滤波使能位1 唤醒滤波器使能0 唤醒滤波器禁止
bit 2-0 PHSEG2相位缓冲段 PS2 长度 2:0(PHSEG2 1) x TQ 注 PS2 的最小有效值为 2 TQ
*/
void MCP2515_SetCNF3(unsigned char data)
{MCP2515_WriteByte(MCP2515_CNF3,data);
}/*
bit 7-5 REQOP2:0请求工作模式的位000 设定为正常工作模式001 设定为休眠模式010 设定为环回模式011 设定为仅监听模式100 设定为配置模式REQOP 位不应设置为其他值因为这些值都是无效的。
注 上电时 REQOP b’111’
bit 4 ABAT中止所有当前报文发送的位1 请求中止所有当前报文发送的缓冲器0 终止对所有报文发送中止的请求
bit 3 OSM单触发模式位1 使能。报文仅尝试发送一次0 禁止。如有需要报文会重新发送。
bit 2 CLKENCLKOUT 引脚使能位1 CLKOUT 引脚使能0 CLKOUT 引脚禁止 引脚处于高阻态
bit 1-0 CLKPRE1:0CLKOUT 引脚预分频比位00 FCLKOUT 系统时钟频率 /101 FCLKOUT 系统时钟频率 /210 FCLKOUT 系统时钟频率 /411 FCLKOUT 系统时钟频率 /8
*/
void MCP2515_SetMode(unsigned char data)
{MCP2515_WriteByte(MCP2515_CANCTRL,data);
}/*
bit 7-5 OPMOD工作模式位 2:0000 器件处于正常工作模式001 器件处于休眠模式010 器件处于环回模式011 器件处于仅监听模式100 器件处于配置模式
bit 4 未用读为 0
bit 3-1 ICOD中断标志代码位 2:0000 无中断001 出错中断010 唤醒中断011 TXB0 中断100 TXB1 中断101 TXB2 中断110 RXB0 中断111 RXB1 中断bit 0 未用读为 0
*/
unsigned char MCP2515_GetCanStatus(void)
{return MCP2515_ReadByte(MCP2515_CANSTAT);
}void MCP2515_SetTXID(unsigned char TxBnID,MCP2515_CanTxMsg *txmsg)
{unsigned char HSID,LSID,EID8,EID0;unsigned int SendId[2];if(txmsg-IDEMCP2515_CAN_Standard){SendId[0]txmsg-StdId;HSID(unsigned char)(SendId[0]3);LSID(unsigned char)((SendId[0]5)0xE0); MCP2515_WriteByte(MCP2515_TXB0SIDH,HSID);MCP2515_WriteByte(MCP2515_TXB0SIDL,LSID); MCP2515_WriteByte(MCP2515_TXB0DLC,txmsg-DLC);}else if(txmsg-IDEMCP2515_CAN_Extended){SendId[0](txmsg-ExtId)18;SendId[1](txmsg-ExtId)0x03FFFF;HSID(unsigned char)(SendId[0]3);LSID((unsigned char)((SendId[0]5)0xE0) | MCP2515_CAN_Extended | (unsigned char)((SendId[1]16)0x03) );EID8(unsigned char)(SendId[1]8);EID0(unsigned char)SendId[1];
// printf(\r\nHSID%x HSID%x EID8%x EID0%x,HSID,LSID,EID8,EID0);MCP2515_WriteByte(MCP2515_TXB0SIDH,HSID);MCP2515_WriteByte(MCP2515_TXB0SIDL,LSID); MCP2515_WriteByte(MCP2515_TXB0EID8,EID8);MCP2515_WriteByte(MCP2515_TXB0EID0,EID0); }
}void MCP2515_SetTXDLC(unsigned char TxBnDLC,MCP2515_CanTxMsg *txmsg)
{if(txmsg-DLC8)txmsg-DLC8;MCP2515_WriteByte(TxBnDLC,txmsg-DLC|0x40);//默认数据帧
}/*
TXBnDM7:TXBnDM0发送缓冲器 n 数据字段字节 m
*/
void MCP2515_SetTXDATA(unsigned char TxBnDm,MCP2515_CanTxMsg *txmsg)
{for(unsigned char i0;itxmsg-DLC;i){MCP2515_WriteByte(TxBnDmi,txmsg-Data[i]);}
}