#include <TWI.h>

Inheritance diagram for Hardware::TWI:

Collaboration diagram for Hardware::TWI:

Public Member Functions
	TWI (uint32_t freq=DEFAULT_FREQ)

virtual bool	acquire ()

virtual bool	release ()

virtual int	read (uint8_t addr, void *buf, size_t count)

virtual int	write (uint8_t addr, iovec_t *vp)

	TWI (uint32_t freq=DEFAULT_FREQ)

virtual bool	acquire ()

virtual bool	release ()

virtual int	read (uint8_t addr, void *buf, size_t count)

virtual int	write (uint8_t addr, iovec_t *vp)

virtual int	write (uint8_t addr, const void *buf, size_t count)

Static Public Attributes
static const uint32_t	DEFAULT_FREQ = 100000L

Protected Types
enum	{ START = 0x08, REP_START = 0x10, ARB_LOST = 0x38, MT_SLA_ACK = 0x18, MT_SLA_NACK = 0x20, MT_DATA_ACK = 0x28, MT_DATA_NACK = 0x30, MR_SLA_ACK = 0x40, MR_SLA_NACK = 0x48, MR_DATA_ACK = 0x50, MR_DATA_NACK = 0x58, MASK = 0xF8, BUS_ERROR = 0x00 }

enum	state_t { IDLE_STATE, BUSY_STATE, WRITE_STATE }

Protected Member Functions
bool	iowait (uint8_t status)

bool	stop_condition ()

void	lock ()

void	unlock ()

Protected Attributes
bool	m_start

Twi *	m_twi

state_t	m_state

volatile bool	m_busy

Static Protected Attributes
static const uint32_t	RETRY_MAX = 100000

Detailed Description

Definition at line 28 of file TWI.h.

Member Enumeration Documentation

anonymous enum

protected

Status codes for Master Transmitter Mode.

Enumerator
START	Start condition transmitted.
REP_START	Repeated start transmitted.
ARB_LOST	Arbitration lost.
MT_SLA_ACK	Slave address/write sent, ACK received.
MT_SLA_NACK	dito, NACK received.
MT_DATA_ACK	Data write sent, ACK received.
MT_DATA_NACK	dito, NACK received.
MR_SLA_ACK	Slave address/read sent, ACK received.
MR_SLA_NACK	dito, NACK received.
MR_DATA_ACK	Data received, ACK sent.
MR_DATA_NACK	dito, NACK sent.
MASK	Mask status code.
BUS_ERROR	Bus error state.

Definition at line 155 of file TWI.h.

enum Hardware::TWI::state_t

protected

Device driver states.

Enumerator
IDLE_STATE
BUSY_STATE
WRITE_STATE

Definition at line 180 of file TWI.h.

Constructor & Destructor Documentation

Hardware::TWI::TWI ( uint32_t freq = DEFAULT_FREQ )

inline

Construct Two-Wire Interface (TWI).

Parameters

[in] freq bus manager clock frequency (HZ).

Definition at line 34 of file TWI.h.

Hardware::TWI::TWI ( uint32_t freq = DEFAULT_FREQ )

inline

Construct Two-Wire Interface (TWI).

Parameters

[in] freq bus manager clock frequency (HZ).

Definition at line 36 of file TWI.h.

Member Function Documentation

virtual bool Hardware::TWI::acquire ( )

inlinevirtual

Start transaction for given device driver. Return true(1) if successful otherwise false(0).

Returns: bool.

Implements TWI.

Definition at line 48 of file TWI.h.

virtual bool Hardware::TWI::acquire ( )

inlinevirtual

Start transaction for given device driver. Return true(1) if successful otherwise false(0).

Returns: bool.

Implements TWI.

Definition at line 59 of file TWI.h.

bool Hardware::TWI::iowait ( uint8_t status )

inlineprotected

Wait for command to complete and check status. Return true(1) if correct status has been reached otherwise false(0).

Parameters

[in] status to be reached.

Returns: bool.

Definition at line 178 of file TWI.h.

void TWI::lock ( )

inlineprotectedinherited

Lock bus manager.

Definition at line 176 of file TWI.h.

virtual int Hardware::TWI::read	(	uint8_t	addr,
		void *	buf,
		size_t	count
	)

inlinevirtual

Read data from device with given address into given buffer.

Parameters

[in]	addr	device address.
[in]	buf	buffer pointer.
[in]	count	buffer size in bytes.

Returns: number of bytes read or negative error code.

Implements TWI.

Definition at line 85 of file TWI.h.

virtual int Hardware::TWI::read	(	uint8_t	addr,
		void *	buf,
		size_t	count
	)

inlinevirtual

Read data from device with given address into given buffer.

Parameters

[in]	addr	device address.
[in]	buf	buffer pointer.
[in]	count	buffer size in bytes.

Returns: number of bytes read or negative error code.

Implements TWI.

Definition at line 94 of file TWI.h.

virtual bool Hardware::TWI::release ( )

inlinevirtual

Stop transaction. Mark the bus as available. Return true(1) if successful otherwise false(0).

Returns: bool.

Implements TWI.

Definition at line 63 of file TWI.h.

virtual bool Hardware::TWI::release ( )

inlinevirtual

Stop transaction. Mark the bus as available. Return true(1) if successful otherwise false(0).

Returns: bool.

Implements TWI.

Definition at line 73 of file TWI.h.

bool Hardware::TWI::stop_condition ( )

inlineprotected

Definition at line 187 of file TWI.h.

void TWI::unlock ( )

inlineprotectedinherited

Unlock bus manager.

Definition at line 185 of file TWI.h.

virtual int Hardware::TWI::write	(	uint8_t	addr,
		iovec_t *	vp
	)

inlinevirtual

Write data to device with from given io vector.

Parameters

[in]	addr	device address.
[in]	vp	io vector pointer.

Returns: number of bytes written or negative error code.

Implements TWI.

Definition at line 123 of file TWI.h.

virtual int Hardware::TWI::write	(	uint8_t	addr,
		iovec_t *	vp
	)

inlinevirtual

Write data to device with from given io vector.

Parameters

[in]	addr	device address.
[in]	vp	io vector pointer.

Returns: number of bytes written or negative error code.

Implements TWI.

Definition at line 134 of file TWI.h.

virtual int TWI::write	(	uint8_t	addr,
		const void *	buf,
		size_t	count
	)

inlinevirtualinherited

Write data to device with given address from given buffer.

Parameters

[in]	addr	device address.
[in]	buf	buffer pointer.
[in]	count	buffer size in bytes.

Returns: number of bytes written or negative error code.

Definition at line 151 of file TWI.h.

Member Data Documentation

const uint32_t TWI::DEFAULT_FREQ = 100000L

staticinherited

Default Two-Wire Interface clock: 100 KHz.

Definition at line 108 of file TWI.h.

volatile bool TWI::m_busy

protectedinherited

Bus manager semaphore.

Definition at line 171 of file TWI.h.

bool Hardware::TWI::m_start

protected

Start condition issued flag.

Definition at line 185 of file TWI.h.

state_t Hardware::TWI::m_state

protected

Definition at line 185 of file TWI.h.

Twi* Hardware::TWI::m_twi

protected

TWI instance (libsam/twi).

Definition at line 177 of file TWI.h.

const uint32_t Hardware::TWI::RETRY_MAX = 100000

staticprotected

Maximum number of retries.

Definition at line 174 of file TWI.h.

The documentation for this class was generated from the following file:

src/Hardware/AVR/TWI.h

Public Member Functions

Static Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation