1.18.10.4 I2Cx_Write Function
C
/* x = I2C instance number */
/* I2C master mode */
bool I2Cx_Write(uint16_t address, uint8_t *pdata, size_t length)
Summary
Writes data to the slave.
Description
This function writes data to a slave on the bus. The function will attempt to write length number of bytes from pdata buffer to a slave whose address is specified by address. The I2C Master will generate a Start condition, write the data and then generate a Stop Condition. If the slave NAKs the request or a bus error was encountered on the bus, the transfer is terminated. The application can call the I2Cx_ErrorGet function to know the cause of the error. The function is non-blocking. It initiates bus activity and returns immediately. The transfer is then completed in the peripheral interrupt. A transfer request cannot be placed when another transfer is in progress. Calling the write function when another function is already in progress will cause the function to return false. If a callback was registered, the library will call the registered callback function when the transfer has completed.
Precondition
I2Cx_Initialize must have been called for the associated I2C instance.
Parameters
Param | Description |
---|---|
address | 7-bit / 10-bit slave address. |
data | pointer to source data buffer that contains the data to betransmitted. |
length | length of data buffer in number of bytes. Also the number of bytesto be written. |
Returns
true - The request was placed successfully and the bus activity was initiated.
false - The request fails, if there was already a transfer in progress when this function was called.
Example
uint8_t myData [NUM_BYTES]; void MyI2CCallback(uintptr_t context) { // This function will be called when the transfer completes. Note // that this function executes in the context of the I2C interrupt. } I2C1_Initialize(); I2C1_CallbackRegister(MyI2CCallback, NULL); if(!I2C1_Write( SLAVE_ADDR, &myData[0], NUM_BYTES )) { // error handling }
Remarks
None.