CAN - Controller Area Network#

CAN_ErrorCode_TypeDef#

CAN_ErrorCode_TypeDef

CAN Status codes.

CAN_Mode_TypeDef#

CAN_Mode_TypeDef

CAN peripheral mode.

CAN_Init#

void CAN_Init (CAN_TypeDef *can, const CAN_Init_TypeDef *init)

Initialize CAN.

CAN_GetClockFrequency#

uint32_t CAN_GetClockFrequency (CAN_TypeDef *can)

Get the CAN module frequency.

An internal prescaler of 2 is inside the CAN module.

Returns

• A clock value.

CAN_MessageLost#

bool CAN_MessageLost (CAN_TypeDef *can, uint8_t interface, uint8_t msgNum)

Read a Message Object to find if a message was lost ; reset the 'Message Lost' flag.

Returns

• True if a message was lost, false otherwise.

CAN_SetRoute#

void CAN_SetRoute (CAN_TypeDef *can, bool active, uint16_t pinRxLoc, uint16_t pinTxLoc)

Set the ROUTE registers.

CAN_SetBitTiming#

void CAN_SetBitTiming (CAN_TypeDef *can, uint32_t bitrate, uint16_t propagationTimeSegment, uint16_t phaseBufferSegment1, uint16_t phaseBufferSegment2, uint16_t synchronisationJumpWidth)

Set the bitrate and its parameters.

Multiple parameters need to be properly configured. See the reference manual for a detailed description. Careful : the BRP (Baud Rate Prescaler) is calculated by: 'brp = freq / (period * bitrate);'. freq is the frequency of the CAN device, period the time of transmission of a bit. The result is an uint32_t. Hence it's truncated, causing an approximation error. This error is non negligible when the period is high, the bitrate is high, and frequency is low.

CAN_SetMode#

void CAN_SetMode (CAN_TypeDef *can, CAN_Mode_TypeDef mode)

Set the CAN operation mode.

In initialization mode, the CAN module is deactivated. Reset the messages in all other modes to be sure that there is no leftover data that needs to be configured before use.

CAN_SetIdAndFilter#

void CAN_SetIdAndFilter (CAN_TypeDef *can, uint8_t interface, bool useMask, const CAN_MessageObject_TypeDef *message, bool wait)

Set the ID and the filter for a specific Message Object.

The initialization bit has to be 0 to use this function.

CAN_ConfigureMessageObject#

void CAN_ConfigureMessageObject (CAN_TypeDef *can, uint8_t interface, uint8_t msgNum, bool valid, bool tx, bool remoteTransfer, bool endOfBuffer, bool wait)

Configure valid, TX/RX, remoteTransfer for a specific Message Object.

The initialization bit has to be 0 to use this function.

CAN_SendMessage#

void CAN_SendMessage (CAN_TypeDef *can, uint8_t interface, const CAN_MessageObject_TypeDef *message, bool wait)

Send data from the Message Object message.

If the message is configured as TX and remoteTransfer = 0, calling this function will send the data of this Message Object if its parameters are correct. If the message is TX and remoteTransfer = 1, this function will set the data of message to RAM and exit. Data will be automatically sent after reception of a remote frame. If the message is RX and remoteTransfer = 1, this function will send a remote frame to the corresponding ID. If the message is RX and remoteTransfer = 0, the user shouldn't call this function. It will also send a remote frame.

CAN_ReadMessage#

bool CAN_ReadMessage (CAN_TypeDef *can, uint8_t interface, CAN_MessageObject_TypeDef *message)

Read data and ID from a Message Object in RAM and store it in a message.

Read the information from RAM on this Message Object. Data and the configuration of the Message Object is read. The information is only read if the message stored in the Message Object is new and valid.

Returns

• True if the Message Object in RAM holds a new and valid message, which was not read earlier, false otherwise.

CAN_AbortSendMessage#

void CAN_AbortSendMessage (CAN_TypeDef *can, uint8_t interface, uint8_t msgNum, bool wait)

Abort sending a message.

Set the TXRQST of the CTRL register to 0. Doesn't touch data or the other parameters. The user can call CAN_SendMessage() to send the object after using CAN_AbortSendMessage().

CAN_ResetMessages#

void CAN_ResetMessages (CAN_TypeDef *can, uint8_t interface)

Reset all Message Objects and set their data to 0.

CAN_Reset#

void CAN_Reset (CAN_TypeDef *can)

Set all CAN registers to RESETVALUE.

Leave the CAN device disabled.

CAN_WriteData#

void CAN_WriteData (CAN_TypeDef *can, uint8_t interface, const CAN_MessageObject_TypeDef *message)

Write data from a message to the MIRx registers.

CAN_SendRequest#

void CAN_SendRequest (CAN_TypeDef *can, uint8_t interface, uint8_t msgNum, bool wait)

Send a request for writing or reading RAM of the Message Object msgNum.

CAN_Enable#

void CAN_Enable (CAN_TypeDef *can, bool enable)

Enable the Host Controller to send messages.

CAN_IsEnabled#

bool CAN_IsEnabled (CAN_TypeDef *can)

Give the communication capabilities state.

Returns

• True if the Host Controller can send messages, false otherwise.

CAN_ReadyWait#

void CAN_ReadyWait (CAN_TypeDef *can, uint8_t interface)

Waiting function.

CAN_GetLastErrorCode#

CAN_ErrorCode_TypeDef CAN_GetLastErrorCode (CAN_TypeDef *can)

Get the last error code and clear its register.

Returns

• return Last error code.

CAN_HasNewdata#

uint32_t CAN_HasNewdata (CAN_TypeDef *can)

Indicate which message objects have received new data.

Returns

• State of MESSAGEDATA register indicating which message objects have received new data.

CAN_StatusIntClear#

void CAN_StatusIntClear (CAN_TypeDef *can, uint32_t flags)

Clear one or more pending CAN status interrupts.

CAN_StatusIntDisable#

void CAN_StatusIntDisable (CAN_TypeDef *can, uint32_t flags)

Disable CAN status interrupts.

CAN_StatusIntEnable#

void CAN_StatusIntEnable (CAN_TypeDef *can, uint32_t flags)

Enable CAN status interrupts.

CAN_StatusIntGet#

uint32_t CAN_StatusIntGet (CAN_TypeDef *can)

Get pending CAN status interrupt flags.

Note

• This function does not clear event bits.

Returns

• CAN interrupt source(s) pending.

CAN_StatusIntGetEnabled#

uint32_t CAN_StatusIntGetEnabled (CAN_TypeDef *can)

Get pending and enabled CAN status interrupt flags.

Note

• This function does not clear event bits.

Returns

• CAN interrupt source(s) pending and enabled.

CAN_StatusIntSet#

void CAN_StatusIntSet (CAN_TypeDef *can, uint32_t flags)

Set one or more CAN status interrupts.

CAN_StatusGet#

uint32_t CAN_StatusGet (CAN_TypeDef *can)

Get CAN status.

Returns

• A value of CAN register STATUS.

CAN_StatusClear#

void CAN_StatusClear (CAN_TypeDef *can, uint32_t flags)

Clear CAN status.

CAN_GetErrorCount#

uint32_t CAN_GetErrorCount (CAN_TypeDef *can)

Get the error count.

Returns

• Error count.

CAN_MessageIntClear#

void CAN_MessageIntClear (CAN_TypeDef *can, uint32_t flags)

Clear one or more pending CAN message interrupts.

CAN_MessageIntDisable#

void CAN_MessageIntDisable (CAN_TypeDef *can, uint32_t flags)

Disable CAN message interrupts.

CAN_MessageIntEnable#

void CAN_MessageIntEnable (CAN_TypeDef *can, uint32_t flags)

Enable CAN message interrupts.

CAN_MessageIntGet#

uint32_t CAN_MessageIntGet (CAN_TypeDef *can)

Get pending CAN message interrupt flags.

Note

• This function does not clear event bits.

Returns

• CAN message interrupt source(s) pending.

CAN_MessageIntGetEnabled#

uint32_t CAN_MessageIntGetEnabled (CAN_TypeDef *can)

Get CAN message interrupt flags that are pending and enabled.

Note

• This function does not clear event bits.

Returns

• CAN message interrupt source(s) pending and enabled.

CAN_MessageIntSet#

void CAN_MessageIntSet (CAN_TypeDef *can, uint32_t flags)

Set one or more CAN message interrupts.

CAN_INIT_DEFAULT#

#define CAN_INIT_DEFAULT

Default initialization of CAN_Init_TypeDef.

The total duration of a bit with these default parameters is 10 tq (time quantum : tq = brp/fsys, brp being the baudrate prescaler and being set according to the wanted bitrate, fsys beeing the CAN device frequency).