2.47.62 FLEXCOMx_TWI_CallbackRegister Function
C
/* x = FLEXCOM instance number */ /* TWI master mode */ void FLEXCOMx_TWI_CallbackRegister(FLEXCOM_TWI_CALLBACK callback, uintptr_t context) /* TWI slave with interrupt enabled */ void FLEXCOMx_TWI_CallbackRegister(FLEXCOM_TWI_SLAVE_CALLBACK callback, uintptr_t context)
Summary
Sets the pointer to the function (and it's context) to be called when the given FLEXCOM TWI's transfer events occur.
Description
This function sets the pointer to a client/application function to be called "back" when the given FLEXCOM TWI's transfer events occur. It also passes a context value (usually a pointer to a context structure) that is passed into the function when it is called. The specified callback function will be called from the peripheral interrupt context.
Precondition
FLEXCOMx_TWI_Initialize must have been called for the associated FLEXCOM TWI instance.
Parameters
| Param | Description |
|---|---|
| callback | A pointer to a function with a calling signature defined by the FLEXCOM_TWI_CALLBACK (in TWI master mode) or FLEXCOM_TWI_SLAVE_CALLBACK (in TWI slave mode) data type. Setting this to NULL disables the callback feature. |
| context | A value (usually a pointer) which is passed (unused) into the function identified by the callback parameter |
Returns
None.
Example
TWI master mode
void FLEXCOM0_TWI_Callback(uintptr_t context) { if(FLEXCOM0_TWI_ErrorGet() == FLEXCOM_TWI_ERROR_NONE) { //Transfer is completed successfully } else { //Error occurred during transfer. } } // Register Callback function which is defined above FLEXCOM0_TWI_CallbackRegister(FLEXCOM0_TWI_Callback, (uintptr_t)0);
TWI slave in non-blocking/interrupt mode
bool FLEXCOM0_TWI_Callback ( FLEXCOM_TWI_SLAVE_TRANSFER_EVENT event, uintptr_t context )
{
uint8_t rxData;
uint8_t txData;
switch(event)
{
case FLEXCOM_TWI_SLAVE_TRANSFER_EVENT_ADDR_MATCH:
// Handle address match event
break;
case FLEXCOM_TWI_SLAVE_TRANSFER_EVENT_RX_READY:
// TWI master is writing data to TWI slave.
// Read the received data byte.
rxData = FLEXCOM0_TWI_ReadByte();
break;
case FLEXCOM_TWI_SLAVE_TRANSFER_EVENT_TX_READY:
// TWI master is reading data from TWI slave.
// Provide data to TWI master.
FLEXCOM0_TWI_WriteByte(txData);
break;
}
}
// Register Callback function which is defined above
FLEXCOM0_TWI_CallbackRegister(FLEXCOM0_TWI_Callback, (uintptr_t)0);
Remarks
When TWI is configured in master mode, the callback function prototype is FLEXCOM_TWI_CALLBACK.
When TWI is configured in slave mode, the callback function prototype is FLEXCOM_TWI_SLAVE_CALLBACK.
