Posted on August 21, 2014 at 20:08Hi,
I am trying to use CANbus on STM32F303VC6. I get it working in loopback mode. But the message is not getting sent in Normal mode. I have turned on SB21 and SB22 to connect the ports PA11 and PA12 to P2. When I debug the code, I find it getting stuck in CAN_TransmitStatus() function due to pending message. Please point out what might be the problem.
#include ''stm32f30x.h''
#include ''stm32f3_discovery.h''
#include ''stm32f30x_it.h''
#include ''stm32f30x_rcc.h''
#include ''stm32f30x_can.h''
#include ''stm32f30x_gpio.h''
#include ''stm32f30x_misc.h''
#include ''CAN.h''
void Init_TxMes(CanTxMsg *TxMessage){
/* Transmit INITIALIZATION*/
TxMessage->IDE = CAN_ID_STD;
TxMessage->DLC = 2;
TxMessage->StdId = 0x321;
TxMessage->RTR = CAN_RTR_DATA;
}
void Init_RxMes(CanRxMsg *RxMessage)
{
uint8_t i = 0;
RxMessage->StdId = 0;
RxMessage->IDE = CAN_ID_STD;
RxMessage->DLC = 0;
RxMessage->FMI = 0;
for (i = 0; i < 8; i++)
{
RxMessage->Data[i] = 0;
}
}
void CAN_setup(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE); //Enable the clock for CAN
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource11 | GPIO_PinSource12 , GPIO_AF_9);
/* Configure CAN1 RX pin */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure CAN1 TX pin */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Enable the CAN global Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = CAN1_SCE_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX1_IRQn;
NVIC_Init(&NVIC_InitStructure);
CAN_DeInit(CAN1);
/* Configure CAN1 **************************************************/
/* Struct init*/
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 = ENABLE;
CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
CAN_InitStructure.CAN_BS1 = CAN_BS1_3tq;
CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
CAN_InitStructure.CAN_Prescaler =6;
/*Initializes the CAN1 */
CAN_Init(CAN1,&CAN_InitStructure);
/*CAN1 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 = 0x6420;
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);
}
int main (void) {
int i;
uint8_t TransmitMailbox = 0;
CAN_setup (); // setup CAN interface
Init_TxMes(&TxMessage);
while(1){
TxMessage.Data[0] = 0xAB;
TxMessage.Data[1] = 0xCD;
TransmitMailbox = CAN_Transmit(CAN1,&TxMessage);
i = 0;
while((CAN_TransmitStatus(CAN1, TransmitMailbox) != CANTXOK) && (i != 0xFF)) // I put a breakpoint here to check and found the message is pending
i++;
}
