#include <SPI.h>

Inheritance diagram for SPI:

Public Types
enum	tFrameMode { kChipSelect, kPreLatchPulse, kPostLatchPulse, kPreAndPostLatchPulse }
enum	tSPIConstants { kReceiveFIFODepth = 512, kTransmitFIFODepth = 512 }
Public Member Functions
	SPI (DigitalOutput &clk, DigitalOutput &mosi, DigitalInput &miso)
	SPI (DigitalOutput clk, DigitalOutput mosi, DigitalInput *miso)
	SPI (DigitalOutput &clk, DigitalOutput &mosi)
	SPI (DigitalOutput clk, DigitalOutput mosi)
	SPI (DigitalOutput &clk, DigitalInput &miso)
	SPI (DigitalOutput clk, DigitalInput miso)
virtual	~SPI ()
void	SetBitsPerWord (UINT32 bits)
UINT32	GetBitsPerWord ()
void	SetClockRate (double hz)
void	SetMSBFirst ()
void	SetLSBFirst ()
void	SetSampleDataOnFalling ()
void	SetSampleDataOnRising ()
void	SetSlaveSelect (DigitalOutput *ss, tFrameMode mode=kChipSelect, bool activeLow=false)
void	SetSlaveSelect (DigitalOutput &ss, tFrameMode mode=kChipSelect, bool activeLow=false)
DigitalOutput *	GetSlaveSelect (tFrameMode mode=NULL, bool activeLow=NULL)
void	SetClockActiveLow ()
void	SetClockActiveHigh ()
virtual void	ApplyConfig ()
virtual UINT16	GetOutputFIFOAvailable ()
virtual UINT16	GetNumReceived ()
virtual bool	IsDone ()
bool	HadReceiveOverflow ()
virtual void	Write (UINT32 data)
virtual UINT32	Read (bool initiate=false)
virtual void	Reset ()
virtual void	ClearReceivedData ()
Protected Attributes
tSPI *	m_spi
tSPI::tConfig	m_config
tSPI::tChannels	m_channels
DigitalOutput *	m_ss
Static Protected Attributes
static SEM_ID	m_semaphore = NULL

Detailed Description

SPI bus interface class.

This class is intended to be used by sensor (and other SPI device) drivers. It probably should not be used directly.

The FPGA only supports a single SPI interface.

Constructor & Destructor Documentation

SPI::SPI	(	DigitalOutput &	clk,
		DigitalOutput &	mosi,
		DigitalInput &	miso
	)

Constructor for input and output.

Parameters:

clk	The digital output for the clock signal.
mosi	The digital output for the written data to the slave (master-out slave-in).
miso	The digital input for the input data from the slave (master-in slave-out).

SPI::SPI	(	DigitalOutput *	clk,
		DigitalOutput *	mosi,
		DigitalInput *	miso
	)

Constructor for input and output.

Parameters:

clk	The digital output for the clock signal.
mosi	The digital output for the written data to the slave (master-out slave-in).
miso	The digital input for the input data from the slave (master-in slave-out).

SPI::SPI	(	DigitalOutput &	clk,
		DigitalOutput &	mosi
	)

Constructor for output only.

Parameters:

clk	The digital output for the clock signal.
mosi	The digital output for the written data to the slave (master-out slave-in).

SPI::SPI	(	DigitalOutput *	clk,
		DigitalOutput *	mosi
	)

Constructor for output only.

Parameters:

clk	The digital output for the clock signal.
mosi	The digital output for the written data to the slave (master-out slave-in).

SPI::SPI	(	DigitalOutput &	clk,
		DigitalInput &	miso
	)

Constructor for input only.

Parameters:

clk	The digital output for the clock signal.
miso	The digital input for the input data from the slave (master-in slave-out).

SPI::SPI	(	DigitalOutput *	clk,
		DigitalInput *	miso
	)

Constructor for input only.

Parameters:

clk	The digital output for the clock signal.
miso	The digital input for the input data from the slave (master-in slave-out).

SPI::~SPI ( ) [virtual]

Destructor.

Member Function Documentation

void SPI::ApplyConfig ( ) [virtual]

Apply configuration settings and reset the SPI logic.

void SPI::ClearReceivedData ( ) [virtual]

Empty the receive FIFO.

UINT32 SPI::GetBitsPerWord ( )

Get the number of bits from each word that the slave transmits or receives.

Returns:: The number of bits in one frame (1 to 32 bits).

UINT16 SPI::GetNumReceived ( ) [virtual]

Get the number of words received and currently available to be read from the receive FIFO.

Returns:: The number of words available to read.

UINT16 SPI::GetOutputFIFOAvailable ( ) [virtual]

Get the number of words that can currently be stored before being transmitted to the device.

Returns:: The number of words available to be written.

DigitalOutput * SPI::GetSlaveSelect	(	tFrameMode *	mode = `NULL`,
		bool *	activeLow = `NULL`
	)

Get the slave select line behavior.

Parameters:

mode	Frame mode: kChipSelect: active for the duration of the frame. kPreLatchPulse: pulses before the transfer of each frame. kPostLatchPulse: pulses after the transfer of each frame. kPreAndPostLatchPulse: pulses before and after each frame.
activeLow	True if slave select line is active low.

Returns:: The slave select digital output.

bool SPI::HadReceiveOverflow ( )

Determine if the receive FIFO was full when attempting to add new data at end of a transfer.

Returns:: True if the receive FIFO overflowed.

bool SPI::IsDone ( ) [virtual]

Have all pending transfers completed?

Returns:: True if no transfers are pending.

UINT32 SPI::Read ( bool initiate = false ) [virtual]

Read a word from the receive FIFO.

Waits for the current transfer to complete if the receive FIFO is empty.

If the receive FIFO is empty, there is no active transfer, and initiate is false, errors.

Parameters:

initiate If true, this function pushes "0" into the transmit buffer and initiates a transfer. If false, this function assumes that data is already in the receive FIFO from a previous write.

void SPI::Reset ( ) [virtual]

Stop any transfer in progress and empty the transmit FIFO.

void SPI::SetBitsPerWord ( UINT32 bits )

Configure the number of bits from each word that the slave transmits or receives.

Parameters:

bits	The number of bits in one frame (1 to 32 bits).

void SPI::SetClockActiveHigh ( )

Configure the clock output line to be active high. This is sometimes called clock polarity low.

void SPI::SetClockActiveLow ( )

Configure the clock output line to be active low. This is sometimes called clock polarity high.

void SPI::SetClockRate ( double hz )

Configure the rate of the generated clock signal. The default and maximum value is 76,628.4 Hz.

Parameters:

hz	The clock rate in Hertz.

void SPI::SetLSBFirst ( )

Configure the order that bits are sent and received on the wire to be least significant bit first.

void SPI::SetMSBFirst ( )

Configure the order that bits are sent and received on the wire to be most significant bit first.

void SPI::SetSampleDataOnFalling ( )

Configure that the data is stable on the falling edge and the data changes on the rising edge.

void SPI::SetSampleDataOnRising ( )

Configure that the data is stable on the rising edge and the data changes on the falling edge.

void SPI::SetSlaveSelect	(	DigitalOutput *	ss,
		tFrameMode	mode = `kChipSelect`,
		bool	activeLow = `false`
	)

Configure the slave select line behavior.

Parameters:

ss	slave select digital output.
mode	Frame mode: kChipSelect: active for the duration of the frame. kPreLatchPulse: pulses before the transfer of each frame. kPostLatchPulse: pulses after the transfer of each frame. kPreAndPostLatchPulse: pulses before and after each frame.
activeLow	True if slave select line is active low.

void SPI::SetSlaveSelect	(	DigitalOutput &	ss,
		tFrameMode	mode = `kChipSelect`,
		bool	activeLow = `false`
	)

Configure the slave select line behavior.

Parameters:

ss	slave select digital output.
mode	Frame mode: kChipSelect: active for the duration of the frame. kPreLatchPulse: pulses before the transfer of each frame. kPostLatchPulse: pulses after the transfer of each frame. kPreAndPostLatchPulse: pulses before and after each frame.
activeLow	True if slave select line is active low.

void SPI::Write ( UINT32 data ) [virtual]

Write a word to the slave device. Blocks until there is space in the output FIFO.

If not running in output only mode, also saves the data received on the MISO input during the transfer into the receive FIFO.

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

SPI.h
SPI.cpp

Public Types

Public Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation