1.35.17.2 TWIx_Write Function

C

/* x = TWI instance number */

/* TWI master mode */
bool TWIx_Write(uint16_t address, uint8_t *pdata, size_t length)

Summary

Writes data to the TWI slave

Description

This function writes data to a TWI 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 TWI 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 TWIx_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

TWIx_Initialize must have been called for the associated TWI instance.

Parameters

Param Description
address 7-bit / 10-bit slave address.
pdata pointer to source data buffer
length length of data buffer in number of bytes.

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];

if(!TWI1_Write( SLAVE_ADDR, &myData[0], NUM_BYTES ))
{
    // error handling
}

Remarks

None.