MityDSP::tcDspI2c Class Reference

Instances of this class handle access to a "generic" implementation of the I2C interface for the MityDSP. More...

#include <core/DspI2c.h>

List of all members.

Public Types
typedef void(*	tfIsrCallback )(tcDspI2c *)
	prototype for the ISR callbacks.
typedef void(*	tfIsrCallbackWithArg )(tcDspI2c *, void *)
Public Member Functions
	tcDspI2c (void *apAddress, int anLevel=gnAutoLevel)
	This constructor is used to open an istance of the DspI2c interface.
	~tcDspI2c ()
	This destructor is used to close up and free the resources tied to the associated I2C interface.
bool	IsDone (void)
	Routine returns true if the previous operation is complete.
bool	IsTxEmpty (void)
	Checks the transmit FIFO to see if it's empty.
bool	IsRxEmpty (void)
	Checks the receive FIFO to see if it's empty.
unsigned int	GetFIFODepth (void)
	Returns the depth of the transmit and receive FIFO.
void	FlushRxFIFO (void)
	This routine will flush the I2C read FIFO.
int	ReadFIFO (unsigned char *apData, int anMaxWords)
	Reads 8-bit words from the receive FIFO until either the FIFO is empty or the maximum specified words have been read.
int	ReadFIFO (unsigned short *apData, int anMaxWords)
	Reads 16-bit words from the receive FIFO until either the FIFO is empty or the maximum specified words have been read.
void	FlushTxFIFO (void)
	This routine will flush the I2C transmit FIFO.
int	WriteFIFO (unsigned char *apData, int anNumWords)
	Writes the specified number of 8-bit words to the transmit FIFO.
int	WriteFIFO (unsigned short *apData, int anNumWords)
	Writes the specified number of 16-bit words to the transmit FIFO.
bool	IssueReadRequest (unsigned char anSlaveAddr, unsigned char anWordAddr, int anNumWords, unsigned int anTimeout=0)
	Posts a read request on the I2C bus.
bool	IssueWriteRequest (unsigned char anSlaveAddr, unsigned char anWordAddr, int anNumWords, unsigned int anTimeout=0)
	Posts a write request on the I2C bus.
void	EnableInterrupt (bool abEnable)
	Sets or clears the I2C interrupt enable.
void	RegisterIsrCallback (tfIsrCallback afCallback)
	Registers the specified ISR callback for the "done" interrupt.
void	RegisterIsrCallback (tfIsrCallbackWithArg afCallback, void *apUserArg=NULL)
	Registers the specified ISR callback for the "done" interrupt.
Static Public Member Functions
static int	interrupt_dispatch (Arg arMyObject)
	Static interrupt dispatch routine.
Public Attributes
unsigned int	mnInterruptCount
	ISR counter (debug).
Protected Member Functions
void	i2cInterrupt (void)
	Interrupt service routine for the I2C class.
Protected Attributes
SEM_Handle	mhMyMutex
	To serialize access.
SEM_Handle	mhDone
	Used to indicate command done.
unsigned int	mnFifoDepth
	depth of firmware FIFO
bool	mbIntState
	state of interrupt enable
tfIsrCallback	mfIsrCallback
	Callback without argument.
tfIsrCallbackWithArg	mfIsrCallbackWithArg
	Callback with argument.
void *	mpUserArg
	User supplied ISR arg.
volatile unsigned int *	mpBaseAddr
	firmware base address
unsigned short	mnMyIntMask
	core interrupt mask
int	mnMyIntLevel
	core interrupt level
int	mnMyIntVector
	core interrupt vector
Static Protected Attributes
static unsigned int	mnTicksPerSec = (1000 * CLK_countspms()) / CLK_getprd()
	Conversion from low resolution.

---

Detailed Description

Instances of this class handle access to a "generic" implementation of the I2C interface for the MityDSP.

See also:

tcDspI2c Page

---

Member Typedef Documentation

typedef void(* MityDSP::tcDspI2c::tfIsrCallback)(tcDspI2c *)

prototype for the ISR callbacks.

typedef void(* MityDSP::tcDspI2c::tfIsrCallbackWithArg)(tcDspI2c *, void *)

---

Constructor & Destructor Documentation

tcDspI2c::tcDspI2c	(	void *	apAddress,
		int	anLevel = gnAutoLevel
	)

This constructor is used to open an istance of the DspI2c interface.

Parameters:

[in]	apAddress	Base Address of I2C core
[in]	anLevel	Optional parameter to force a chained interrupt at the specified level.

Returns:

None.

See also:

DspI2c.h

tcDspI2c::~tcDspI2c

(

)

This destructor is used to close up and free the resources tied to the associated I2C interface.

Returns:

None.

See also:

DspI2c.h

---

Member Function Documentation

int tcDspI2c::interrupt_dispatch

(

Arg

ahMyObject

)

[static]

Static interrupt dispatch routine.

Required because of the hidden this pointer associated with a member function, which cannot be passed directly to the interrupt dispatcher.

Parameters:

[in]

ahMyObject

The "this->" pointer for the instance of tcDspI2c associated with this ISR.

Returns:

0

bool tcDspI2c::IsDone

(

void

)

Routine returns true if the previous operation is complete.

Returns:

true if the "done" bit is set, false otherwise

See also:

DspI2c.h

bool tcDspI2c::IsTxEmpty

(

void

)

Checks the transmit FIFO to see if it's empty.

Returns:

true if the FIFO is empty, false otherwise

See also:

DspI2c.h

bool tcDspI2c::IsRxEmpty

(

void

)

Checks the receive FIFO to see if it's empty.

Returns:

true if the FIFO is empty, false otherwise

See also:

DspI2c.h

unsigned int tcDspI2c::GetFIFODepth

(

void

)

Returns the depth of the transmit and receive FIFO.

Both FIFOs have the same depth.

Returns:

The depth (in words) of the FIFOs.

See also:

DspI2c.h

void tcDspI2c::FlushRxFIFO

(

void

)

This routine will flush the I2C read FIFO.

It is useful when a clearing operation is require or after initialization.

Returns:

None.

See also:

DspI2c.h

int tcDspI2c::ReadFIFO	(	unsigned char *	apData,
		int	anMaxWords
	)

Reads 8-bit words from the receive FIFO until either the FIFO is empty or the maximum specified words have been read.

Parameters:

[out]	apData	Pointer to storage for the received data.
[in]	anMaxWords	Maximum words to store in apData.

Returns:

Number of words of data actually stored.

See also:

DspI2c.h

int tcDspI2c::ReadFIFO	(	unsigned short *	apData,
		int	anMaxWords
	)

Reads 16-bit words from the receive FIFO until either the FIFO is empty or the maximum specified words have been read.

Parameters:

[out]	apData	Pointer to storage for the received data.
[in]	anMaxWords	Maximum words to store in apData.

Returns:

Number of words of data actually stored.

See also:

DspI2c.h

void tcDspI2c::FlushTxFIFO

(

void

)

This routine will flush the I2C transmit FIFO.

It is useful when a clearing operation is require or after initialization.

Returns:

None.

See also:

DspI2c.h

int tcDspI2c::WriteFIFO	(	unsigned char *	apData,
		int	anNumWords
	)

Writes the specified number of 8-bit words to the transmit FIFO.

Note:

The routine limits the number of words written to the depth of the transmit FIFO. It is up to the application to ensure that the FIFO is empty before writing.

Parameters:

[in]	apData	Pointer to the data to transmit.
[in]	anNumWords	Number of words in apData.

Returns:

Number of words of data actually written.

See also:

DspI2c.h

int tcDspI2c::WriteFIFO	(	unsigned short *	apData,
		int	anNumWords
	)

Writes the specified number of 16-bit words to the transmit FIFO.

Note:

The routine limits the number of words written to the depth of the transmit FIFO. It is up to the application to ensure that the FIFO is empty before writing.

Parameters:

[in]	apData	Pointer to the data to transmit.
[in]	anNumWords	Number of words in apData.

Returns:

Number of words of data actually written.

See also:

DspI2c.h

bool tcDspI2c::IssueReadRequest	(	unsigned char	anSlaveAddr,
		unsigned char	anWordAddr,
		int	anNumWords,
		unsigned int	anTimeout = 0
	)

Posts a read request on the I2C bus.

The address of the slave device, the word address within the device, and the number of sequential words to read are provided.

If a non-zero timeout is provided, the routine waits for the specified number of milliseconds for the request to complete.

Note:

It is up to the application to ensure enough words exist in the receive FIFO to hold the requested data.

Parameters:

[in]	anSlaveAddr	Address of device on I2C bus
[in]	anWordAddr	Address of word to read within selected device
[in]	anNumWords	Number of words to read sequentially from device
[in]	anTimeout	Time (in millisecs) to wait for completion

Returns:

True if operation completed, false otherwise.

See also:

DspI2c.h

bool tcDspI2c::IssueWriteRequest	(	unsigned char	anSlaveAddr,
		unsigned char	anWordAddr,
		int	anNumWords,
		unsigned int	anTimeout = 0
	)

Posts a write request on the I2C bus.

The address of the slave device, the word address within the device, and the number of sequential words to write are provided.

If a non-zero timeout is provided, the routine waits for the specified number of milliseconds for the request to complete.

Note:

It is up to the application to pre-load the write FIFO with the appropriate number of words of data.

Parameters:

[in]	anSlaveAddr	Address of device on I2C bus
[in]	anWordAddr	Address of word to write within selected device
[in]	anNumWords	Number of words to write sequentially to device
[in]	anTimeout	Time (in millisecs) to wait for completion

Returns:

True if operation completed, false otherwise.

See also:

DspI2c.h

void tcDspI2c::EnableInterrupt

(

bool

abEnable

)

Sets or clears the I2C interrupt enable.

Returns:

None.

See also:

DspI2c.h

void tcDspI2c::RegisterIsrCallback

(

tfIsrCallback

afCallback

)

Registers the specified ISR callback for the "done" interrupt.

Parameters:

[in]

afCallback

The callback to associate with the interrupt (or NULL for none).

Returns:

None.

See also:

DspI2c.h

void tcDspI2c::RegisterIsrCallback	(	tfIsrCallbackWithArg	afCallback,
		void *	apUserArg = NULL
	)

Registers the specified ISR callback for the "done" interrupt.

Parameters:

[in]	afCallback	The callback to associate with the interrupt (or NULL for none).
[in]	apUserArg	An argument to be supplied with the callback.

Returns:

None.

See also:

DspI2c.h

void tcDspI2c::i2cInterrupt

(

void

)

[protected]

Interrupt service routine for the I2C class.

The ISR reads and clears any pending done interrupt and sets the internal semaphore. If an interrupts callback is registered, the routine is called.

"Interrupt-ness" is taken care of by the 'dispatcher' in DSP/BIOS. Installed by the constructor.

---

Member Data Documentation

unsigned int MityDSP::tcDspI2c::mnInterruptCount

ISR counter (debug).

unsigned int tcDspI2c::mnTicksPerSec = (1000 * CLK_countspms()) / CLK_getprd() [static, protected]

Conversion from low resolution.

SEM_Handle MityDSP::tcDspI2c::mhMyMutex [protected]

To serialize access.

SEM_Handle MityDSP::tcDspI2c::mhDone [protected]

Used to indicate command done.

unsigned int MityDSP::tcDspI2c::mnFifoDepth [protected]

depth of firmware FIFO

bool MityDSP::tcDspI2c::mbIntState [protected]

state of interrupt enable

tfIsrCallback MityDSP::tcDspI2c::mfIsrCallback [protected]

Callback without argument.

tfIsrCallbackWithArg MityDSP::tcDspI2c::mfIsrCallbackWithArg [protected]

Callback with argument.

void* MityDSP::tcDspI2c::mpUserArg [protected]

User supplied ISR arg.

volatile unsigned int* MityDSP::tcDspI2c::mpBaseAddr [protected]

firmware base address

unsigned short MityDSP::tcDspI2c::mnMyIntMask [protected]

core interrupt mask

int MityDSP::tcDspI2c::mnMyIntLevel [protected]

core interrupt level

int MityDSP::tcDspI2c::mnMyIntVector [protected]

core interrupt vector