Controller area network (CAN) routines

UM0459

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2.2.19

CAN_WaitEndOfTx function

2.2.20

CAN_GetMsgReceiveStatus

Example:

This example illustrates how to test the new data registers for the message object 0.

{

/*Test if a message is pending in the receive message object 0*/

if (CAN_GetMsgReceiveStatus(CAN1, 0))

{

/* Receive the message from this message object (i.e. get its data from message

RAM)*/

}

}

Table 23.

CAN_WaitEndOfTx function description

Function name

CAN_WaitEndOfTx

Function prototype

void CAN_WaitEndOfTx(CAN_TypeDef* CAN);

Behavior description

Waits until current transmission is finished.

This function should be called between two consecutive transmissions

to ensure the latest frame has been completely transmitted on the bus,

and therefore cannot be aborted anymore. A timeout should be added to

avoid the infinite state if an error occurs.

Input parameter

Pointer to a CAN1 or CAN2 CAN structure.

Output parameter

None

Return value

None

Required preconditions

A message must have been sent before.

Called functions

None

Table 24.

CAN_GetMsgReceiveStatus function description

Function name

CAN_GetMsgReceiveStatus

Prototype

FlagStatus CAN_GetMsgReceiveStatus(CAN_TypeDef* CAN, u16

msgobj);

Behavior description

Tests the waiting status of a received message by reading the

corresponding bit in the NewData 1 or 2 registers.

Input parameter 1

CAN: pointer to a CAN1 or CAN2 CAN_TypeDef structure.

Input parameter 2

msgobj: message object number, from 0 to 31.

Output parameter

None

Return value

1 if the corresponding message object has received a message

awaiting to be copied, else 0.

Required preconditions

The corresponding message object must have been set as RX.

Called functions

None