Question
Can bus not working in normal mode
Posted on January 31, 2014 at 23:25
Hello, Iam working on my can project with discovery f429 kit. Now I have it conneced to MCP2551 transciever and to NI-CAN reader (as far as I know it should act as 2. node as it is sending acknowledgment)
Iam fine with loopback mode. I can read the data from NI-CAN and also I can receive them looped at my board. So it looks like can is working perfectly with baudrate and GPIO output. Problem is when I want to go normal mode. It does nothing. Iam initialising it as loopback and at the end of all peripheral init I switch it to normal mode. Thank you for help :)AN_InitTypeDef CAN_InitStructure;
void CAN_RCC_Configuration(void)
{
/* CAN1 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);
/* CAN2 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN2, ENABLE);
/* Init CAN GPIO clocks */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
}
void CAN_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructureCAN_RX;
GPIO_InitTypeDef GPIO_InitStructureCAN_TX;
/* GPIO CAN_RX Configuration */
GPIO_InitStructureCAN_RX.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructureCAN_RX.GPIO_Mode = GPIO_Mode_AF;
//GPIO_InitStructureCAN_RX.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructureCAN_RX.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOB, &GPIO_InitStructureCAN_RX);
/* GPIO CAN_TX Configuration */
GPIO_InitStructureCAN_TX.GPIO_Pin = GPIO_Pin_13;
GPIO_InitStructureCAN_TX.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructureCAN_TX.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructureCAN_TX.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructureCAN_TX.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_Init(GPIOB, &GPIO_InitStructureCAN_TX);
/* Connect CAN_RX & CAN_TX to AF9 */
GPIO_PinAFConfig(GPIOB, GPIO_PinSource12, GPIO_AF_CAN2); //CAN_RX = PB12
GPIO_PinAFConfig(GPIOB, GPIO_PinSource13, GPIO_AF_CAN2); //CAN_TX = PB13
}
void CAN_Configuration(void)
{
/* CAN2 reset */
CAN_DeInit(CAN2);
/* CAN2 configuration */
CAN_InitStructure.CAN_TTCM = DISABLE; // time-triggered communication mode = DISABLED
CAN_InitStructure.CAN_ABOM = DISABLE; // automatic bus-off management mode = DISABLED
CAN_InitStructure.CAN_AWUM = DISABLE; // automatic wake-up mode = DISABLED
CAN_InitStructure.CAN_NART = DISABLE; // non-automatic retransmission mode = DISABLED
CAN_InitStructure.CAN_RFLM = DISABLE; // receive FIFO locked mode = DISABLED
CAN_InitStructure.CAN_TXFP = DISABLE; // transmit FIFO priority = DISABLED
//CAN_InitStructure.CAN_Mode = CAN_Mode_LoopBack; // Debug can mode
CAN_InitStructure.CAN_Mode = CAN_Mode_LoopBack; // Debug can mode
CAN_InitStructure.CAN_SJW = CAN_SJW_1tq; // synchronization jump width = 1
CAN_InitStructure.CAN_BS1 = CAN_BS1_12tq; //10
CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq; //4
CAN_InitStructure.CAN_Prescaler = 6; // baudrate 500 kbps APB1 = 45MHz tq + tq*BS1 + tq*BS2 73%
CAN_Init(CAN2, &CAN_InitStructure);
}
void CAN_SetFilter(void)
{
CAN_FilterInitTypeDef CAN_FilterInitStructure;
CAN_InitTypeDef CAN_InitStructure;
/* Default filter - accept all to CAN_FIFO*/
CAN_InitStructure.CAN_Mode = CAN_OperatingMode_Initialization; // Can to init mode
CAN_FilterInitStructure.CAN_FilterActivation = DISABLE; // Disable filter
CAN_FilterInitStructure.CAN_FilterNumber = 14; // 0..13 for CAN1, .27 for CAN2
CAN_FilterInitStructure.CAN_FilterFIFOAssignment = CAN_FIFO0;
CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_16bit;
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);
// este nastavit 11 bitove ID
}
void CAN_SetNVIC(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_InitStructure.NVIC_IRQChannel = CAN2_RX0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
CAN_ITConfig(CAN2, CAN_IT_FMP0, ENABLE);
}
uint8_t CAN_Tq_CMD(int16_t torque)
{
CanTxMsg TxMessage;
TxMessage.StdId = REG_R_RX;
TxMessage.ExtId = 0x0;
TxMessage.RTR = CAN_RTR_DATA;
TxMessage.IDE = CAN_ID_STD;
TxMessage.DLC = 3;
TxMessage.Data[0] = REGID_TQ_CMD;
TxMessage.Data[1] = (uint8_t)torque;
TxMessage.Data[2] = (uint8_t)(torque>>8);
CAN_Transmit(CAN2, &TxMessage);
if(CAN_TransmitStatus(CAN2, 0)) return 0;
else return 1;
}
int16_t CAN_RxMessage(void)
{
CanRxMsg RxMessage;
int16_t torque = 0;
CAN_Receive(CAN2,CAN_FIFO0,&RxMessage);
if((RxMessage.Data[0]) == REGID_TQ_CMD)
{
torque |= RxMessage.Data[1];
torque |= RxMessage.Data[2]<<8;
}
return torque;
}
void initCan(void)
{
// Init clock
CAN_RCC_Configuration();
// Init GPIO pins
CAN_GPIO_Init();
// CAN Configuration
CAN_Configuration();
// Messages id configuration
CAN_SetFilter();
// Enable message interrupt
CAN_SetNVIC();
CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
CAN_Init(CAN2, &CAN_InitStructure);
}