I2C Slave Driver

Overview

Data Structures
struct	i2c_slave_address_t
	Data structure with 7-bit Slave address and Slave address disable. More...
struct	i2c_slave_config_t
	Structure with settings to initialize the I2C slave module. More...

Enumerations
enum	_i2c_slave_flags {   kI2C_SlavePendingFlag = I2C_STAT_SLVPENDING_MASK,   kI2C_SlaveNotStretching,   kI2C_SlaveSelected = I2C_STAT_SLVSEL_MASK,   kI2C_SaveDeselected }
	I2C slave peripheral flags. More...
enum	i2c_slave_address_register_t {   kI2C_SlaveAddressRegister0 = 0U,   kI2C_SlaveAddressRegister1 = 1U,   kI2C_SlaveAddressRegister2 = 2U,   kI2C_SlaveAddressRegister3 = 3U }
	I2C slave address register. More...
enum	i2c_slave_address_qual_mode_t {   kI2C_QualModeMask = 0U,   kI2C_QualModeExtend }
	I2C slave address match options. More...
enum	i2c_slave_bus_speed_t
	I2C slave bus speed options. More...

Slave initialization and deinitialization
void	I2C_SlaveGetDefaultConfig (i2c_slave_config_t *slaveConfig)
	Provides a default configuration for the I2C slave peripheral. More...
status_t	I2C_SlaveInit (I2C_Type *base, const i2c_slave_config_t *slaveConfig, uint32_t srcClock_Hz)
	Initializes the I2C slave peripheral. More...
void	I2C_SlaveSetAddress (I2C_Type *base, i2c_slave_address_register_t addressRegister, uint8_t address, bool addressDisable)
	Configures Slave Address n register. More...
void	I2C_SlaveDeinit (I2C_Type *base)
	Deinitializes the I2C slave peripheral. More...
static void	I2C_SlaveEnable (I2C_Type *base, bool enable)
	Enables or disables the I2C module as slave. More...

Slave status
static void	I2C_SlaveClearStatusFlags (I2C_Type *base, uint32_t statusMask)
	Clears the I2C status flag state. More...

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Data Structure Documentation

struct i2c_slave_address_t

Data Fields
uint8_t	address
	7-bit Slave address SLVADR. More...
bool	addressDisable
	Slave address disable SADISABLE. More...

Field Documentation

uint8_t i2c_slave_address_t::address

bool i2c_slave_address_t::addressDisable

struct i2c_slave_config_t

This structure holds configuration settings for the I2C slave peripheral. To initialize this structure to reasonable defaults, call the I2C_SlaveGetDefaultConfig() function and pass a pointer to your configuration structure instance.

The configuration structure can be made constant so it resides in flash.

Data Fields
i2c_slave_address_t	address0
	Slave's 7-bit address and disable. More...
i2c_slave_address_t	address1
	Alternate slave 7-bit address and disable. More...
i2c_slave_address_t	address2
	Alternate slave 7-bit address and disable. More...
i2c_slave_address_t	address3
	Alternate slave 7-bit address and disable. More...
i2c_slave_address_qual_mode_t	qualMode
	Qualify mode for slave address 0. More...
uint8_t	qualAddress
	Slave address qualifier for address 0. More...
i2c_slave_bus_speed_t	busSpeed
	Slave bus speed mode. More...
bool	enableSlave
	Enable slave mode. More...

Field Documentation

i2c_slave_address_t i2c_slave_config_t::address0

i2c_slave_address_t i2c_slave_config_t::address1

i2c_slave_address_t i2c_slave_config_t::address2

i2c_slave_address_t i2c_slave_config_t::address3

i2c_slave_address_qual_mode_t i2c_slave_config_t::qualMode

uint8_t i2c_slave_config_t::qualAddress

i2c_slave_bus_speed_t i2c_slave_config_t::busSpeed

If the slave function stretches SCL to allow for software response, it must provide sufficient data setup time to the master before releasing the stretched clock. This is accomplished by inserting one clock time of CLKDIV at that point. The busSpeed value is used to configure CLKDIV such that one clock time is greater than the tSU;DAT value noted in the I2C bus specification for the I2C mode that is being used. If the busSpeed mode is unknown at compile time, use the longest data setup time kI2C_SlaveStandardMode (250 ns)

bool i2c_slave_config_t::enableSlave

Enumeration Type Documentation

enum _i2c_slave_flags

Note

These enums are meant to be OR'd together to form a bit mask.

Enumerator
kI2C_SlavePendingFlag	The I2C module is waiting for software interaction.
kI2C_SlaveNotStretching	Indicates whether the slave is currently stretching clock (0 = yes, 1 = no).
kI2C_SlaveSelected	Indicates whether the slave is selected by an address match.
kI2C_SaveDeselected	Indicates that slave was previously deselected (deselect event took place, w1c).

enum i2c_slave_address_register_t

Enumerator
kI2C_SlaveAddressRegister0	Slave Address 0 register.
kI2C_SlaveAddressRegister1	Slave Address 1 register.
kI2C_SlaveAddressRegister2	Slave Address 2 register.
kI2C_SlaveAddressRegister3	Slave Address 3 register.

enum i2c_slave_address_qual_mode_t

Enumerator
kI2C_QualModeMask	The SLVQUAL0 field (qualAddress) is used as a logical mask for matching address0.
kI2C_QualModeExtend	The SLVQUAL0 (qualAddress) field is used to extend address 0 matching in a range of addresses.

enum i2c_slave_bus_speed_t

Function Documentation

void I2C_SlaveGetDefaultConfig

(

i2c_slave_config_t *

slaveConfig

)

This function provides the following default configuration for the I2C slave peripheral:

*  slaveConfig->enableSlave = true;
*  slaveConfig->address0.disable = false;
*  slaveConfig->address0.address = 0u;
*  slaveConfig->address1.disable = true;
*  slaveConfig->address2.disable = true;
*  slaveConfig->address3.disable = true;
*  slaveConfig->busSpeed = kI2C_SlaveStandardMode;
* 

After calling this function, override any settings to customize the configuration, prior to initializing the master driver with I2C_SlaveInit(). Be sure to override at least the address0.address member of the configuration structure with the desired slave address.

Parameters

[out]

slaveConfig

User provided configuration structure that is set to default values. Refer to i2c_slave_config_t.

status_t I2C_SlaveInit	(	I2C_Type *	base,
		const i2c_slave_config_t *	slaveConfig,
		uint32_t	srcClock_Hz
	)

This function enables the peripheral clock and initializes the I2C slave peripheral as described by the user provided configuration.

Parameters

base	The I2C peripheral base address.
slaveConfig	User provided peripheral configuration. Use I2C_SlaveGetDefaultConfig() to get a set of defaults that you can override.
srcClock_Hz	Frequency in Hertz of the I2C functional clock. Used to calculate CLKDIV value to provide enough data setup time for master when slave stretches the clock.

void I2C_SlaveSetAddress	(	I2C_Type *	base,
		i2c_slave_address_register_t	addressRegister,
		uint8_t	address,
		bool	addressDisable
	)

This function writes new value to Slave Address register.

Parameters

base	The I2C peripheral base address.
addressRegister	The module supports multiple address registers. The parameter determines which one shall be changed.
address	The slave address to be stored to the address register for matching.
addressDisable	Disable matching of the specified address register.

void I2C_SlaveDeinit

(

I2C_Type *

base

)

This function disables the I2C slave peripheral and gates the clock. It also performs a software reset to restore the peripheral to reset conditions.

Parameters

base	The I2C peripheral base address.

static void I2C_SlaveEnable ( I2C_Type *  base, bool  enable  )

inlinestatic

Parameters

base	The I2C peripheral base address.
enable	True to enable or flase to disable.

static void I2C_SlaveClearStatusFlags ( I2C_Type *  base, uint32_t  statusMask  )

inlinestatic

The following status register flags can be cleared:

• slave deselected flag

Attempts to clear other flags has no effect.

Parameters

base	The I2C peripheral base address.
statusMask	A bitmask of status flags that are to be cleared. The mask is composed of _i2c_slave_flags enumerators OR'd together. You may pass the result of a previous call to I2C_SlaveGetStatusFlags().

See Also

_i2c_slave_flags.