【ST学习小组】STM32F103的CAN 通信之主控器

原帖地址：http://www.eefocus.com/bbs/article_244_380394.html

本CAN主要实现两个芯片的通讯，主控器通过CAN将获得的从控制发来的数据，通过串口显示在上位机上，在上位机上实时得到一个数据曲线。从控制器通过AD获得数据。

以下是主控制器的代码程序：

本主程序主要分为三个，main.c led.c usart.c can.c

main.c

#include "stm32f10x.h"

#include "misc.h"

#include "led.h"

#include "key.h"

#include "usart.h"

//#include "exti.h"

#include "can.h"

void RCC_Configuration(void);

void Delay(__IO uint32_t nCount);

//___________________Global Variable declare________

u8 CAN_TransmitDataBuf[8];

u8 ADC_num=0;

u16 ADC_Data0[10];

u16 ADC_Data1[10];

u16 ADC_Data2[10];

u16 ADC_Data3[10];

//______________________________________________

//___________________________ADC modue__________

void Adc_Init(void)

{

//先初始化IO口

RCC->APB2ENR|=1<<2; //使能PORTA口时钟

GPIOA->CRL&=0XFFFF0000;//PA0 1 2 3 anolog输入

//通道10/11设置

RCC->APB2ENR|=1<<9; //ADC1时钟使能

RCC->APB2RSTR|=1<<9; //ADC1复位

RCC->APB2RSTR&=~(1<<9);//复位结束

RCC->CFGR&=~(3<<14); //分频因子清零

//SYSCLK/DIV2=12M ADC时钟设置为12M,ADC最大时钟不能超过14M!

//否则将导致ADC准确度下降!

RCC->CFGR|=2<<14;

ADC1->CR1&=0XF0FFFF; //工作模式清零

ADC1->CR1|=0<<16; //独立工作模式

ADC1->CR1&=~(1<<8); //非扫描模式

ADC1->CR2&=~(1<<1); //单次转换模式

ADC1->CR2&=~(7<<17);

ADC1->CR2|=7<<17; //软件控制转换

ADC1->CR2|=1<<20; //使用用外部触发(SWSTART)!!!必须使用一个事件来触发

ADC1->CR2&=~(1<<11); //右对齐

ADC1->SQR1&=~(0XF<<20);

ADC1->SQR1&=0<<20;

//设置通道0~3的采样时间

ADC1->SMPR2&=0XFFFFF000;//通道0,1,2,3采样时间清空

ADC1->SMPR2|=7<<9; //通道3 239.5周期,提高采样时间可以提高精确度

ADC1->SMPR2|=7<<6; //通道2 239.5周期,提高采样时间可以提高精确度

ADC1->SMPR2|=7<<3; //通道1 239.5周期,提高采样时间可以提高精确度

ADC1->SMPR2|=7<<0; //通道0 239.5周期,提高采样时间可以提高精确度

ADC1->CR2|=1<<0; //开启AD转换器

ADC1->CR2|=1<<3; //使能复位校准

while(ADC1->CR2&1<<3); //等待校准结束

//该位由软件设置并由硬件清除。在校准寄存器被初始化后该位将被清除。

ADC1->CR2|=1<<2; //开启AD校准

while(ADC1->CR2&1<<2); //等待校准结束

//该位由软件设置以开始校准，并在校准结束时由硬件清除

}

//获得ADC值

//ch:通道值 0~3

u16 Get_Adc(u8 ch)

{

//设置转换序列

ADC1->SQR3&=0XFFFFFFE0;//规则序列1 通道ch

ADC1->SQR3|=ch;

ADC1->CR2|=1<<22; //启动规则转换通道

while(!(ADC1->SR&1<<1));//等待转换结束

return ADC1->DR;//返回adc值

}

//_________________________________________________

//_____________________ADC 采样值发送________

void ADC_TransmitByCan(u16 Data_CH1,u16 Data_CH2,u16 Data_CH3)

{

}

//////////////////////////////////////////////////////////////////////////////////

//int i=0;

//定时器3中断服务程序

void TIM3_IRQHandler(void)

{

u8 index=0;

u16 Max=0;

u16 Min=0xFF;

u32 ADC0_sum=0;

if(TIM3->SR&0X0001)//溢出中断

{

// ADC_Data1[1]=Get_Adc(ADC_Channel_1);

// ADC_Data2[2]=Get_Adc(ADC_Channel_2);

ADC_Data0[ADC_num]=Get_Adc(ADC_Channel_0);

ADC_num++;

if (ADC_num>=9)

{

ADC_num=0;

for(index=0;index<9;index++)

{

if(ADC_Data0[index]>Max)

{

Max=ADC_Data0[index];

}

if(ADC_Data0[index]<Min)

{

Min=ADC_Data0[index];

}

ADC0_sum+=(u32) (ADC_Data0[index]);

}

ADC0_sum=(ADC0_sum-Max-Min)/8;

CAN_TransmitDataBuf[1]=(ADC0_sum&0x00ff);

CAN_TransmitDataBuf[0]=((ADC0_sum>>8)&0x00ff);

CAN_TransmitData(2,CAN_TransmitDataBuf,0xAAAA);

}

}

TIM3->SR&=~(1<<0);//清除中断标志位

}

//通用定时器中断初始化

//这里时钟选择为APB1的2倍，而APB1为36M

//arr：自动重装值。

//psc：时钟预分频数

//这里使用的是定时器3!

void Timer_init(u16 arr,u16 psc)

{

NVIC_InitTypeDef NVIC_InitStructure;

RCC->APB1ENR|=1<<1;//TIM3时钟使能

TIM3->ARR=arr; //设定计数器自动重装值//刚好1ms

TIM3->PSC=psc; //预分频器7200,得到10Khz的计数时钟

//这两个东东要同时设置才可以使用中断

TIM3->DIER|=1<<0; //允许更新中断

TIM3->DIER|=1<<6; //允许触发中断

TIM3->CR1|=0x01; //使能定时器3

/* Configure the NVIC Preemption Priority Bits */

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

/* Enable the USART1 Interrupt */

NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
//设置串口中断

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

}

//_______________________________________________

int main(void)

{

RCC_Configuration(); //系统时钟配置

LED_GPIO_Config(); //led配置

KEY_GPIO_Config(); //按键配置

USART_Init_Config(); //串口配置

// EXTI_Init_Config();

// Adc_Init();

CAN_Init_Config();

//Timer_init(50,6400);

while (1)

{

LED1_ON;

LED2_ON;

Delay(0xFFFFF);

Delay(0xFFFFF);

}

}

void RCC_Configuration(void)

{

/* Setup the microcontroller system. Initialize the Embedded Flash Interface,

initialize the PLL and update the SystemFrequency variable. */

SystemInit();

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO|RCC_APB2Periph_GPIOB,ENABLE); //打开重映射时钟

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); /* GPIOA clock enable */

//RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); /* GPIOB clock enable */

RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE); /* CAN Periph clock enable */

}

void Delay(__IO uint32_t nCount)

{

for(; nCount != 0; nCount--);

}

#ifdef USE_FULL_ASSERT

/**

* @brief Reports the name of the source file and the source line number

* where the assert_param error has occurred.

* @param file: pointer to the source file name

* @param line: assert_param error line source number

* @retval : None

*/

void assert_failed(uint8_t* file, uint32_t line)

{

/* User can add his own implementation to report the file name and line number,

ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

/* Infinite loop */

while (1)

{

}

}

#endif

-------------------------------------------------------------------------------------------------------------------------------

usart.c #include "usart.h" USART_InitTypeDef USART_InitStruct; USART_ClockInitTypeDef USART_ClockInitStruct; void USART1_GPIO_Config(void) { GPIO_InitTypeDef GPIO_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA , ENABLE); //USART1 TX GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出 GPIO_Init(GPIOA, &GPIO_InitStructure); //A端口 //USART1 RX GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; //复用开漏输入 GPIO_Init(GPIOA, &GPIO_InitStructure); } void USART1_NVIC_Configuration(void) { NVIC_InitTypeDef NVIC_InitStructure; /* Configure the NVIC Preemption Priority Bits */ NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0); /* Enable the USART1 Interrupt */ NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; //设置串口中断 NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; NVIC_Init(&NVIC_InitStructure); } void USART_Config(USART_TypeDef* USARTx) { USART_InitTypeDef USART_InitStructure; USART_InitStructure.USART_BaudRate = 115200; //速率115200bps USART_InitStructure.USART_WordLength = USART_WordLength_8b;//数据位8位 USART_InitStructure.USART_StopBits = USART_StopBits_1;//停止位1位 USART_InitStructure.USART_Parity = USART_Parity_No;//无校验位 USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; //无硬件流控 USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;//收发模式 /* Configure USART1 */ USART_Init(USARTx, &USART_InitStructure); //配置串口参数函数 /* Enable USART1 Receive and Transmit interrupts */ USART_ITConfig(USART1, USART_IT_RXNE, ENABLE); //使能接收中断 //USART_ITConfig(USART1, USART_IT_TXE, ENABLE); //使能发送缓冲空中断 //USART_ITConfig(USART1, USART_IT_TC, ENABLE); //使能发送完成中断 /* Enable the USART1 */ USART_Cmd(USART1, ENABLE); } void USART_Init_Config(void) { USART1_GPIO_Config(); //端口配置 USART_Config(USART1); //数据格式配置 USART1_NVIC_Configuration(); //中断配置 } void Usart_transmitByte(uint8_t Usart_TransmitDatebuf) { USART1->DR=Usart_TransmitDatebuf; while((USART1->SR&0X40)==0);//wait } void Usart_TransmitData(u16 Usart_TransmitDataLength,uint8_t * Usart_TransmitDatebuf) { u16 Usart_Transmitindex; //_____________________send the start byte_______________________ Usart_transmitByte(0xFF); Usart_transmitByte(0x00); // _____________________send the end byte________________________ for(Usart_Transmitindex=0;Usart_Transmitindex<Usart_TransmitDataLength;Usart_Transmitindex++) { if(Usart_TransmitDatebuf[Usart_Transmitindex]==0xFF) { if(Usart_TransmitDatebuf[Usart_Transmitindex+1]==0x00) { Usart_transmitByte(0xFF); Usart_transmitByte(0x00); Usart_transmitByte(0xFF); Usart_transmitByte(0x00); Usart_Transmitindex++; } else { Usart_transmitByte(Usart_TransmitDatebuf[Usart_Transmitindex]); } } else { Usart_transmitByte(Usart_TransmitDatebuf[Usart_Transmitindex]); } } //___________________End Transmit Data________________________ Usart_transmitByte(0xFF); Usart_transmitByte(0x00); //_____________________date Usart_transmitByte(0x00); }

-------------------------------------------------------------------------------------------------------------------------------------------------

led.c #include "led.h" void LED_GPIO_Config(void) { GPIO_InitTypeDef GPIO_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOD , ENABLE); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2; //LED1 V6 //将V6,V7,V8 配置为通用推挽输出 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //口线翻转速度为50MHz GPIO_Init(GPIOA, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1; //LED1 V6 //将V6,V7,V8 配置为通用推挽输出 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //口线翻转速度为50MHz GPIO_Init(GPIOA, &GPIO_InitStructure); }

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

can.c

#include "can.h"

u16 ret;

/******************CAN1中断配置函数*********************************************/

//优先级：0

//中断服务程序：USB_LP_CAN1_RX0_IRQn------stm32f10x_it.

void CAN_NVIC_Configuration(void)

{

NVIC_InitTypeDef NVIC_InitStructure;

/* Enable CAN1 RX0 interrupt IRQ channel */

NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

}

/******************CAN1端口配置函数*********************************************/

//引脚：CAN1RX-PA8、CAN1Tx-PB8

//说明：开启端口B的时钟、CAN1的时钟

void CAN_GPIO_Configuration(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

/* 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_Speed=GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_Init(GPIOA, &GPIO_InitStructure);

/*端口重映射到PB8、PB9上*/

// GPIO_PinRemapConfig(GPIO_Remap2_CAN1, ENABLE); //配置CAN总线为从映射

RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE); /* CAN Periph clock enable */

}

/******************CAN1查询接受配置函数*****************************************/

//波特率：SJW-1tq、BS1-8tq、BS2-7tq、Prescaler-5;

//

u8 CAN_Polling(void)

{

CAN_InitTypeDef CAN_InitStructure;

CAN_FilterInitTypeDef CAN_FilterInitStructure;

CanTxMsg TxMessage;

CanRxMsg RxMessage;

uint32_t i = 0;

uint8_t TransmitMailbox = 0;

/* CAN register init */

CAN_DeInit(CAN1);

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;

CAN_Init(CAN1, &CAN_InitStructure);

/* 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;

CAN_FilterInitStructure.CAN_FilterIdLow=0x0000;

CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0x0000;

CAN_FilterInitStructure.CAN_FilterMaskIdLow=0x0000;

CAN_FilterInitStructure.CAN_FilterFIFOAssignment=0;

CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;

CAN_FilterInit(&CAN_FilterInitStructure);

/* transmit */

TxMessage.StdId=0x11;

TxMessage.RTR=CAN_RTR_DATA;

TxMessage.IDE=CAN_ID_STD;

TxMessage.DLC=2;

TxMessage.Data[0]=0xAA;

TxMessage.Data[1]=0xAA;

TransmitMailbox=CAN_Transmit(CAN1, &TxMessage);

i = 0;

while((CAN_TransmitStatus(CAN1, TransmitMailbox) != CANTXOK) && (i != 0xFF))

{

i++;

}

i = 0;

while((CAN_MessagePending(CAN1, CAN_FIFO0) < 1) && (i != 0xFF))

{

i++;

}

/* receive */

RxMessage.StdId=0x00;

RxMessage.IDE=CAN_ID_STD;

RxMessage.DLC=0;

RxMessage.Data[0]=0x00;

RxMessage.Data[1]=0x00;

CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);

if( (RxMessage.StdId!=0x11)|(RxMessage.StdId!=0x12) )

{

return 1;

}

if (RxMessage.IDE!=CAN_ID_STD)

{

return 1;

}

if (RxMessage.DLC!=2)

{

return 1;

}

if ((RxMessage.Data[0]<<8|RxMessage.Data[1])!=0xCAFE)

{

return 1;

}

return 0; /* Test Passed */

}

/******************CAN1中断接受配置函数*****************************************/

//波特率：SJW-1tq、BS1-8tq、BS2-7tq、Prescaler-5;

//

void CAN_Interrupt(void)

{

CAN_InitTypeDef CAN_InitStructure;

CAN_FilterInitTypeDef CAN_FilterInitStructure;

/* CAN register init */

CAN_DeInit(CAN1);

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_Normal;
//Normal

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=1;

CAN_Init(CAN1, &CAN_InitStructure);

/* CAN filter init */

CAN_FilterInitStructure.CAN_FilterNumber=1;

CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;

CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;

CAN_FilterInitStructure.CAN_FilterIdHigh=0x0000;

CAN_FilterInitStructure.CAN_FilterIdLow=0x0000;

CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0x0000;

CAN_FilterInitStructure.CAN_FilterMaskIdLow=0x0000;

CAN_FilterInitStructure.CAN_FilterFIFOAssignment=CAN_FIFO0;

CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;

CAN_FilterInit(&CAN_FilterInitStructure);

/* CAN FIFO0 message pending interrupt enable */

CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE); //CAN 中断使能

}

/******************CAN1数据传送函数*******************************************/

//

//

void CAN_TransmitData(u8 DataLength,u8 *Data_Buf,u32 ID) /* transmit 1 message */

{

CanTxMsg TxMessage;

u8 CAN_Transmitindex=0;

TxMessage.StdId=ID;

TxMessage.ExtId=ID;

TxMessage.IDE=CAN_ID_EXT;

TxMessage.RTR=CAN_RTR_DATA;

//_______________Set Data length _________________

TxMessage.DLC=DataLength;

for(CAN_Transmitindex=0;CAN_Transmitindex<DataLength;CAN_Transmitindex++)

{

TxMessage.Data[CAN_Transmitindex]=Data_Buf[CAN_Transmitindex];

}

//_____________________________________________

CAN_Transmit(CAN1, &TxMessage);

}

void CAN_Init_Config(void)

{

CAN_NVIC_Configuration(); //中断配置

CAN_GPIO_Configuration(); //端口配置

CAN_Interrupt(); //中断接受配置

}