STM32学习笔记---CAN实验

三文鱼之妙恋 2011-05-11

展开全文

继做了DAC实验后，继续进行第15个实验-CAN实验,本实验 Can总线的环回测试，LED2亮----说明100k/S 的轮询方式收发正常。LED3亮----说明500k/S 的中断方式收发正常。

typedef enum {FAILED = 0, PASSED = !FAILED} TestStatus;

__IO uint32_t CANFLAG = 0;
volatile TestStatus TestRx;

TestStatus CAN_Polling(void);
TestStatus CAN_Interrupt(void);

//can设置初始化
void CAN_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_PinRemapConfig(GPIO_Remap1_CAN1 , ENABLE);

}

TestStatus CAN_Polling(void)
{
CAN_InitTypeDef CAN_InitStructure;
CAN_FilterInitTypeDef CAN_FilterInitStructure;
CanTxMsg TxMessage;
CanRxMsg RxMessage;
uint32_t i = 0;
uint8_t TransmitMailbox = 0;

CAN_DeInit(CAN1);
CAN_StructInit(&CAN_InitStructure);

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_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);

TxMessage.StdId=0x11;
TxMessage.RTR=CAN_RTR_DATA;
TxMessage.IDE=CAN_ID_STD;
TxMessage.DLC=2;
TxMessage.Data[0]=0xCA;
TxMessage.Data[1]=0xFE;

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++;
}

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)
{
return FAILED;
}

if (RxMessage.IDE!=CAN_ID_STD)
{
return FAILED;
}

if (RxMessage.DLC!=2)
{
return FAILED;
}

if ((RxMessage.Data[0]<<8|RxMessage.Data[1])!=0xCAFE)
{
return FAILED;
}

return PASSED;
}

TestStatus CAN_Interrupt(void)
{
CAN_InitTypeDef CAN_InitStructure;
CAN_FilterInitTypeDef CAN_FilterInitStructure;
CanTxMsg TxMessage;
uint32_t i = 0;

CAN_DeInit(CAN1);
CAN_StructInit(&CAN_InitStructure);

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_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);

TxMessage.StdId=0x00;
TxMessage.ExtId=0x1234;
TxMessage.IDE=CAN_ID_EXT;
TxMessage.RTR=CAN_RTR_DATA;
TxMessage.DLC=2;
TxMessage.Data[0]=0xDE;
TxMessage.Data[1]=0xCA;
CAN_Transmit(CAN1, &TxMessage);

CANFLAG = 0xFF;


i=0;
while((CANFLAG == 0xFF) && (i < 0xFFF))
{
    i++;
}

if (i == 0xFFF)
{
    CANFLAG=0;
}

CAN_ITConfig(CAN1, CAN_IT_FMP0, DISABLE);

return (TestStatus)CANFLAG;
}

//测试CAN
void TEST_CAN(void)
{

TestRx = CAN_Polling();

if (TestRx == FAILED)
{

    GPIO_SetBits(GPIOB, GPIO_Pin_5);
}
else
{

    GPIO_SetBits(GPIOD, GPIO_Pin_6);
}

TestRx = CAN_Interrupt();

if (TestRx == FAILED)
{

    GPIO_SetBits(GPIOB, GPIO_Pin_5);
}
else
{

    GPIO_SetBits(GPIOD, GPIO_Pin_3);
}
}

**************

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);

NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
************************

void USB_LP_CAN1_RX0_IRQHandler(void)
{
CanRxMsg RxMessage;

RxMessage.StdId=0x00;
RxMessage.ExtId=0x00;
RxMessage.IDE=0;
RxMessage.DLC=0;
RxMessage.FMI=0;
RxMessage.Data[0]=0x00;
RxMessage.Data[1]=0x00;

CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);

if((RxMessage.ExtId==0x1234) && (RxMessage.IDE==CAN_ID_EXT)
     && (RxMessage.DLC==2) && ((RxMessage.Data[1]|RxMessage.Data[0]<<8)==0xDECA))
{
    CANFLAG = 1;
}
else
{
    CANFLAG = 0;
}
}