GPIO_PinRemapConfig(GPIO_Remap2_CAN1, ENABLE);

    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);

// enable clock to CANs
RCC->APB1ENR |= RCC_APB1ENR_CAN1EN;
RCC->APB1ENR |= RCC_APB1ENR_CAN2EN;

CAN1->MCR |= CAN_MCR_RESET;
CAN2->MCR |= CAN_MCR_RESET;

// configure CANs
CANEnterConfig();

CAN1->MCR |= CAN_MCR_NART;//CAN_MCR_TXFP;
CAN2->MCR |= CAN_MCR_NART;//CAN_MCR_TXFP;

switch (baud_rate) {
case CAN_BR_50KBPS:
BrpVal = (FPBA1 / (TS1VAL + 1 + TS2VAL + 1 + 1)) / 50000UL;
break;
case CAN_BR_125KBPS:
BrpVal = (FPBA1 / (TS1VAL + 1 + TS2VAL + 1 + 1)) / 125000UL;
break;
case CAN_BR_250KBPS:
BrpVal = (FPBA1 / (TS1VAL + 1 + TS2VAL + 1 + 1)) / 250000UL;
break;
case CAN_BR_500KBPS:
BrpVal = (FPBA1 / (TS1VAL + 1 + TS2VAL + 1 + 1)) / 500000UL;
break;
case CAN_BR_1000KBPS:
BrpVal = (FPBA1 / (TS1VAL + 1 + TS2VAL + 1 + 1)) / 1000000UL;
break;
default:
break;
}

CAN1->BTR = (SJWVAL << 24) | (TS2VAL << 20) | (TS1VAL << 16) | (BrpVal - 1);
CAN2->BTR = (SJWVAL << 24) | (TS2VAL << 20) | (TS1VAL << 16) | (BrpVal - 1);

CAN1->IER = CAN_IER_FMPIE0;
CAN2->IER = CAN_IER_FMPIE0;

CAN1->MCR &= ~CAN_MCR_SLEEP;
CAN2->MCR &= ~CAN_MCR_SLEEP;

CANExitConfig();

static void CANExitConfig(void) {
CAN1->MCR &= ~CAN_MCR_INRQ;
// wait while CAN entered to initialization mode
while (CAN1->MSR & CAN_MSR_INAK)
;
CAN2->MCR &= ~CAN_MCR_INRQ;
// wait while CAN entered to initialization mode
while (CAN2->MSR & CAN_MSR_INAK)
;
}

static void CANEnterConfig(void) {
// CAN to initialization mode
CAN1->MCR |= CAN_MCR_INRQ;

// wait while CAN entered to initialization mode
while (!(CAN1->MSR & CAN_MSR_INAK))
;
// CAN to initialization mode
CAN2->MCR |= CAN_MCR_INRQ;
// wait while CAN entered to initialization mode
while (!(CAN2->MSR & CAN_MSR_INAK))
;
}

// begin of configuring filters
    CANEnterConfig();

    CAN1->FMR |= CAN_FMR_FINIT; // set Initialization mode for filter banks
    CAN1->FMR &= ~(0x3F << 8);
    CAN1->FMR |= (0x0E << 8);
    CAN1->FA1R &= ~(uint32_t) (1 << filterIndex); // deactivate filter

    // initialize filter
    CAN1->FS1R |= (uint32_t) (1 << filterIndex);// set 32-bit scale configuration
    CAN1->FM1R &= ~(uint32_t) (1 << filterIndex);// set 2 32-bit identifier list mode

    CAN1->sFilterRegister[filterIndex].FR1 = CAN_msgId; //  32-bit identifier
    CAN1->sFilterRegister[filterIndex].FR2 = CAN_msgMask; //  32-bit identifier
    CAN1->FFA1R &= ~(uint32_t) (1 << filterIndex); // assign filter to FIFO 0
    CAN1->FA1R |= (uint32_t) (1 << filterIndex); // activate filter
    CAN1->FMR &= ~CAN_FMR_FINIT; // reset Initialization mode for filter banks

    CANExitConfig();

void CAN_Initialization (uint16_t speed)
{
CAN_InitTypeDef CAN_InitStructure;
CAN_FilterInitTypeDef CAN_FilterInitStructure;



CAN_DBGFreeze(CAN1,DISABLE);
CAN_DBGFreeze(CAN2,DISABLE);

CAN_DeInit(CAN1);
CAN_DeInit(CAN2);

CAN_InitStructure.CAN_TTCM = DISABLE;
CAN_InitStructure.CAN_ABOM = ENABLE;
CAN_InitStructure.CAN_AWUM = DISABLE;
CAN_InitStructure.CAN_NART = DISABLE;
CAN_InitStructure.CAN_RFLM = DISABLE;
CAN_InitStructure.CAN_TXFP = ENABLE;
CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
CAN_InitStructure.CAN_BS1 = CAN_BS1_16tq;
CAN_InitStructure.CAN_BS2 = CAN_BS2_8tq;

switch (speed)
{
case 1000: CAN_InitStructure.CAN_Prescaler =1; break; //1Mb
case 500: CAN_InitStructure.CAN_Prescaler =1; break; //500 kB
case 250: CAN_InitStructure.CAN_Prescaler =2; break; //250 kB
case 125: CAN_InitStructure.CAN_Prescaler =4; break; //125 kB
case 100: CAN_InitStructure.CAN_Prescaler =6; break; //100 kB
case 50: CAN_InitStructure.CAN_Prescaler =12; break; //50 kB
case 20: CAN_InitStructure.CAN_Prescaler =40; break; //20 kB
case 10: CAN_InitStructure.CAN_Prescaler =62; break; //10 kB
default: CAN_InitStructure.CAN_Prescaler =144; break;
}

CAN_DBGFreeze(CAN1,DISABLE);
CAN_DBGFreeze(CAN2,DISABLE);

CAN_Start(UP);
CAN_Start(DOWN);

CAN_Init(CAN1, &CAN_InitStructure);
CAN_Init(CAN2, &CAN_InitStructure);

//Ôèëüòð âåðõíåãî CAN
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 = 0;
CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
CAN_FilterInit(&CAN_FilterInitStructure);



//CAN_FilterInitStructure.CAN_FilterIdHigh =0x2460;
CAN_FilterInitStructure.CAN_FilterNumber = 15;
CAN_FilterInit(&CAN_FilterInitStructure);

}

/*=========================================================================*/
void NVIC_CAN_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
NVIC_InitStructure.NVIC_IRQChannel=USB_LP_CAN1_RX0_IRQn;//|USB_HP_CAN1_TX_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
/*==============================================================================*/
void USB_HP_CAN1_TX_IRQHandler (void)
{
if (CAN_GetITStatus(CAN1,CAN_IT_TME))
{ // request completed mbx 0
CAN_ClearITPendingBit(CAN1,CAN_IT_TME);
CAN_TxRdy++;
}
}
/*========================================================================*/
void USB_LP_CAN1_RX_IRQHandler (void)
{
if (CAN_GetITStatus(CAN1,CAN_IT_FMP0))
{ // message pending ?
CAN_Receive(CAN1,0,&RxMessage); // read the message
CAN_RxRdy++; // set receive flag
}
}
/*===========================================================================*/
int main (void)
{
__disable_irq ();
Init_CLK();
NVIC_CAN_Configuration();
Init_GPIO_CAN();
Init_CAN();

CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);
CAN_ITConfig(CAN1, CAN_IT_FF0, ENABLE);
CAN_ITConfig(CAN1, CAN_IT_FOV0, ENABLE);
__enable_irq ();
while (1)
{
}
}

#define CAN_GPIO_PORT             GPIOD
#define CAN_RX_SOURCE           GPIO_PinSource0
#define CAN_TX_SOURCE           GPIO_PinSource1
#define CAN_AF_PORT           GPIO_AF_CAN1      
#define CAN_RX_PIN           GPIO_Pin_5
#define CAN_TX_PIN           GPIO_Pin_13



  /* Connect CAN pins to AF9 */
  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_RX_SOURCE, CAN_AF_PORT);
  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_TX_SOURCE, CAN_AF_PORT);
  
  /* Configure CAN RX and TX pins */
  GPIO_InitStructure.GPIO_Pin = CAN_RX_PIN | CAN_TX_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
  GPIO_Init(CAN_GPIO_PORT, &GPIO_InitStructure);