I2C Master peripheral

The section describes the programming interface of the I2C master mode Peripheral driver. More...

Data Structures
struct	i2c_device_t
	Information necessary to communicate with an I2C slave device. More...
struct	i2c_master_t
	Internal driver state information. More...

Enumerations
enum	i2c_direction_t {   kI2CRead = 1,   kI2CWrite = 0 }
	Constants for the direction of an I2C transfer. More...
enum	_i2c_transfer_flags {   kI2CNoStart = 1 << 1,   kI2CNoStop = 1 << 2 }
	Optional flags to control a transfer. More...

I2C Master
void	i2c_master_init (uint32_t instance, i2c_master_t *master)
	Initialize the I2C master mode driver. More...
void	i2c_master_shutdown (i2c_master_t *master)
	Shut down the driver. More...
i2c_status_t	i2c_master_configure_bus (i2c_master_t *master, const i2c_device_t *device)
	Configure the I2C bus to access a device. More...
i2c_status_t	i2c_master_transfer_basic (i2c_master_t *master, uint32_t flags, i2c_direction_t direction, uint8_t *data, size_t dataLength, size_t *actualLengthTransferred, uint32_t timeout_ms)
	Low-level I2C transfer function. More...
i2c_status_t	i2c_master_transfer (i2c_master_t *master, const i2c_device_t *device, i2c_direction_t direction, bool stopAfterTransfer, uint32_t subaddress, size_t subaddressLength, uint8_t *data, size_t dataLength, size_t *actualLengthTransferred, uint32_t timeout_ms)
	Perform a blocking read or write transaction on the I2C bus. More...

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Data Structure Documentation

struct i2c_device_t

Data Fields
uint8_t	address
	The slave's 7-bit address. More...
uint32_t	baudRate_kbps
	The baud rate in kbps to use with this slave device. More...

Field Documentation

uint8_t i2c_device_t::address

uint32_t i2c_device_t::baudRate_kbps

struct i2c_master_t

Note

The contents of this structure are internal to the driver and should not be modified by users. Also, contents of the structure are subject to change in future releases.

Data Fields
uint32_t	instance
bool	isTransferInProgress
uint32_t	flags
i2c_direction_t	direction
uint8_t *	data
volatile size_t	dataRemainingCount
volatile size_t	bytesTransferredCount
volatile bool	gotNak
uint32_t	lastBaudRate_kbps
sync_object_t	irqSync

Enumeration Type Documentation

enum i2c_direction_t

Enumerator
kI2CRead	Read from slave device.
kI2CWrite	Write to slave device.

enum _i2c_transfer_flags

Enumerator
kI2CNoStart	Set this flag to prevent sending a START signal.
kI2CNoStop	Set this flag to prevent sending a STOP signal.

Function Documentation

void i2c_master_init	(	uint32_t	instance,
		i2c_master_t *	master
	)

Parameters

instance	The I2C peripheral instance number.
master	The pointer to the I2C master driver state structure.

void i2c_master_shutdown

(

i2c_master_t *

master

)

Parameters

master

The pointer to the I2C master driver state structure.

i2c_status_t i2c_master_configure_bus	(	i2c_master_t *	master,
		const i2c_device_t *	device
	)

Parameters

master	The pointer to the I2C master driver state structure.
device	The pointer to the I2C device information struct.

i2c_status_t i2c_master_transfer_basic	(	i2c_master_t *	master,
		uint32_t	flags,
		i2c_direction_t	direction,
		uint8_t *	data,
		size_t	dataLength,
		size_t *	actualLengthTransferred,
		uint32_t	timeout_ms
	)

Parameters

master	The pointer to the I2C master driver state structure.
flags	The flags to control a transfer.
direction	The direction of an I2C transfer.
data	The pointer to the data to be transfered.
dataLength	The length in bytes of the data to be transfered.
actualLengthTransferred	The length in bytes of the data thansfered.
timeous_ms	A timeout for the transfer in microseconds.

i2c_status_t i2c_master_transfer	(	i2c_master_t *	master,
		const i2c_device_t *	device,
		i2c_direction_t	direction,
		bool	stopAfterTransfer,
		uint32_t	subaddress,
		size_t	subaddressLength,
		uint8_t *	data,
		size_t	dataLength,
		size_t *	actualLengthTransferred,
		uint32_t	timeout_ms
	)

Parameters

master	The pointer to the I2C master driver state structure.
device	The pointer to the I2C device information struct.
direction	The direction of an I2C transfer.
stopAfterTransfer	Send STOP signal after this transfer or not.
subaddress	The subaddress for a device if it has.
subaddressLength	The length of the subaddress.
data	The pointer to the data to be transfered.
dataLength	The length in bytes of the data to be transfered.
actualLengthTransferred	The length in bytes of the data thansfered.
timeous_ms	A timeout for the transfer in microseconds.