MityDSP::tcDspPwm Class Reference

Instances of this class handle configuring, and enabling the MityDSP Pulse Width Modulator core I/O interface. More...

#include <core/DspPwm.h>

List of all members.

Public Member Functions
	tcDspPwm (void *apAddress, tcDspPwmConfig *=NULL)
	This constructor is used to open a PWM core instance.
	~tcDspPwm ()
	Default destructor.
void	Enable (bool Enable)
	Enable PWM Core (top level enable, for all pulses).
void	SetMode (bool IsContinuous)
	Configure PWM Operating Mode.
void	SetTrigger (bool IsExternalTriggered)
	Configure PWM Trigger Mode.
int	EnableInterrupt (bool Enable, SEM_Handle *apHandle=NULL)
	Configure the PWM Core to generate interrupts on Fixed Cycle (or one shot) completion.
void	ClearFC (void)
	Utility function to clear the Fixed Cycle Completion bit.
unsigned int	ConfigurePulse (unsigned int Pulse, unsigned short Delay, unsigned short OnTime, unsigned short Period)
	Pulse Configuration.
void	EnablePulse (unsigned int Pulse, bool Enabled)
	Enable Specified PWM Pulse.
int	SetTotalClockDivisor (unsigned int Divisor)
	Configure the input clock division length.
int	SetFixedCycleDuration (unsigned int NumCycles)
	Set the runtime for fixed-cycle or one-shot mode of operation.
bool	IsEnabled (void)
	Check if PWM Core is enabled.
bool	IsContinuous (void)
	Check if PWM Core is configured for continuous pulse operation.
bool	IsExtTriggered (void)
	Check if PWM Core is configured for external trigger operation.
bool	IsIntEnabled (void)
	Check if PWM Core has fixed cycle interrupts enabled.
bool	IsFixedCycleComplete (void)
	Check if PWM Fixed Cycle complete flag is set.
int	GetPulseConfig (unsigned int Pulse, unsigned short &Delay, unsigned short &OnTime, unsigned short &Period)
	Gathers pulse configuration parameters from the PWM Core Module.
bool	IsPulseEnabled (unsigned int Pulse)
	Checks whether a specified pulse ID is enabled.
unsigned int	GetTotalClockDivisor (void)
	Retrieve the input clock division length.
unsigned int	GetFixedCycleDuration (void)
	Returns the runtime for fixed-cycle or one-shot mode of operation.
Static Public Member Functions
static int	interrupt_dispatch (Arg arMyObject)
	Static interrupt dispatch routine.
Public Attributes
unsigned int	mnInterruptCount
	ISR counter (useful for debug).
Protected Member Functions
void	pwmInterrupt (void)
	Interrupt service routine for the PWM core.
Protected Attributes
SEM_Handle *	mpMySemaphore
	Pointer to registered semaphores.
volatile unsigned int *	mpMyBaseReg
	PWM Core base register.
unsigned short	mnMyIntMask
	PWM Core interrupt mask.
int	mnMyIntLevel
	PWM Core interrupt level.
int	mnMyIntVector
	PWM Core interrupt vector.
Static Protected Attributes
static const int	gnVerOffset = 0
	Version Register Offset.
static const int	gnCsrOffset = 1
	Control / Status Register Offset.
static const int	gnCdrOffset = 2
	Cycle Duration Register Offset.
static const int	gnPulseOffset = 3
	offset to first pulse register
static const int	gnPulseSize = 3
	num registers per pulse
static const int	gnDROffset = 0
	offset to DR from PulseOffset
static const int	gnCROffset = 1
	offset to DR from PulseOffset
static const int	gnPROffset = 2
	offset to DR from PulseOffset

---

Detailed Description

Instances of this class handle configuring, and enabling the MityDSP Pulse Width Modulator core I/O interface.

Each PWM Core provides for up 5 configurable pulses to be generated/controlled. The routing of the pulse outputs (and optional input trigger) are application specific. See the application FPGA hardware design notes for further information.

The PWM tcDspPwm module does provide an interrupt interface when used in fixed cycle / one-shot mode. The ISR notifies the application via a counting semaphore.

See also:

tcDspPwm Page

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Constructor & Destructor Documentation

tcDspPwm::tcDspPwm	(	void *	apAddress,
		tcDspPwmConfig *	apConfig = NULL
	)

This constructor is used to open a PWM core instance.

The base address and default configuration data are provided.

Parameters:

[in]	apAddress	The base address of the GPIO core.
[in]	apConfig	The configuration structure (optional).

Returns:

None.

See also:

DspGpio.h

tcDspPwm::~tcDspPwm

(

)

Default destructor.

---

Member Function Documentation

int tcDspPwm::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 tcDspGpio associated with this ISR.

Returns:

0

void tcDspPwm::Enable

(

bool

Enable

)

Enable PWM Core (top level enable, for all pulses).

Parameters:

[in]

Enable

When true, core pulse generation is enabled.

Returns:

None

void tcDspPwm::SetMode

(

bool

IsContinuous

)

Configure PWM Operating Mode.

Parameters:

[in]

IsContinuous

When true the core will generate continuous pulse trains (after initial delay conditions are met). When false, core will run until fixed cycle duration has expired.

Returns:

None

void tcDspPwm::SetTrigger

(

bool

IsExternalTriggered

)

Configure PWM Trigger Mode.

Parameters:

[in]

IsExternalTriggered

When true, the core will be configured to start generating pulses when a rising edge is seen on the provided external trigger port of the core. When false, the core will generate pulses immediately (given it is enabled).

Returns:

None

int tcDspPwm::EnableInterrupt	(	bool	Enable,
		SEM_Handle *	apHandle = NULL
	)

Configure the PWM Core to generate interrupts on Fixed Cycle (or one shot) completion.

Parameters:

[in]	Enable	When true, interrupts on Fixed Cycle completion are enabled.
[in]	apHandle	When Enable is true, the apHandle semaphore will be incremented by the PWM interrupt handler. When enable is false, this parameter is ignored. If the apHandle is NULL, no change will be made to the handler.

Returns:

non-zero if a change to the interrupt handler was made. Zero otherwise.

void tcDspPwm::ClearFC

(

void

)

Utility function to clear the Fixed Cycle Completion bit.

If interrupts are enabled, the FC bit is automatically cleared by the ISR Routine. This is provided to the user for polled applications only.

Returns:

None.

unsigned int tcDspPwm::ConfigurePulse	(	unsigned int	Pulse,
		unsigned short	Delay,
		unsigned short	OnTime,
		unsigned short	Period
	)

Pulse Configuration.

This method allows for configuration of the pulse generator parameters.

Parameters:

[in]	Pulse	Pulse to configure. Range 0 to DSP_PWM_NUMPULSES-1
[in]	Delay	Number of divided clocks to delay initial Pulse Period following trigger event
[in]	OnTime	Number of divided clocks to enable pulse
[in]	Period	Number of divided clocks to repeat Pulse Period

Returns:

non-zero on error (bad pulse number, bad OnTime/Period combos, etc.). zero otherwise.

void tcDspPwm::EnablePulse	(	unsigned int	Pulse,
		bool	Enable
	)

Enable Specified PWM Pulse.

Parameters:

[in]	Pulse	Pulse to configure. Range 0 to DSP_PWM_NUMPULSES-1
[in]	Enable	When true pulse will be enabled.

Returns:

None.

int tcDspPwm::SetTotalClockDivisor

(

unsigned int

Divisor

)

Configure the input clock division length.

This routine allows tuning of the effective pulse width frequency clock as a function of the core input clock. E.G., with an input clock of 25 Mhz, a divisor setting of 25 will result in 1 usec increments for all of the pulse settings.

Parameters:

[in]

Divisor

Pulse to configure. Range DSP_PWM_MINCLOCKCYCLES to DSP_PWM_MINCLOCKCYCLES+15. (currently 18 to 33)

Returns:

non-zero on error (illegal Divisor setting).

int tcDspPwm::SetFixedCycleDuration

(

unsigned int

NumCycles

)

Set the runtime for fixed-cycle or one-shot mode of operation.

Parameters:

[in]

NumCycles

The number of cycles to run before FC bit is set. Range from 0 to DSP_PWM_MAXDURATION.

Returns:

non-zero on error (illegal cycle length).

bool tcDspPwm::IsEnabled

(

void

)

Check if PWM Core is enabled.

Returns:

true if the core is enabled.

bool tcDspPwm::IsContinuous

(

void

)

Check if PWM Core is configured for continuous pulse operation.

Returns:

true if the core is in continuous mode. False if in fixed cycle mode.

bool tcDspPwm::IsExtTriggered

(

void

)

Check if PWM Core is configured for external trigger operation.

Returns:

true if the core triggering is fired from external source.

bool tcDspPwm::IsIntEnabled

(

void

)

Check if PWM Core has fixed cycle interrupts enabled.

Returns:

true if interrupts are enabled.

bool tcDspPwm::IsFixedCycleComplete

(

void

)

Check if PWM Fixed Cycle complete flag is set.

Returns:

true if flag is set.

int tcDspPwm::GetPulseConfig	(	unsigned int	Pulse,
		unsigned short &	Delay,
		unsigned short &	OnTime,
		unsigned short &	Period
	)

Gathers pulse configuration parameters from the PWM Core Module.

Parameters:

[in]	Pulse	The Pulse to query, 0 to DSP_PWM_NUMPULSES-1
[out]	Delay	The delay configured for the pulse
[out]	OnTime	The OnTime configured for the pulse
[out]	Period	The Period configured for the pulse

Returns:

non-zero of error (illegal pulse ID).

bool tcDspPwm::IsPulseEnabled

(

unsigned int

Pulse

)

Checks whether a specified pulse ID is enabled.

Parameters:

[in]

Pulse

Pulse ID to check.

Returns:

true of the pulse ID is enabled. false if the pulse ID is not enabled or the pulse ID is illegal.

unsigned int tcDspPwm::GetTotalClockDivisor

(

void

)

Retrieve the input clock division length.

This routine returns the effective pulse width frequency clock as a function of the core input clock. E.g., with an input clock of 25 Mhz, a divisor setting of 25 will result in 1 usec increments for all of the pulse settings.

Returns:

the current setting.

unsigned int tcDspPwm::GetFixedCycleDuration

(

void

)

Returns the runtime for fixed-cycle or one-shot mode of operation.

Returns:

the number of cycles fixed-cycle mode will run in.

void tcDspPwm::pwmInterrupt

(

void

)

[protected]

Interrupt service routine for the PWM core.

The ISR reads and clears any pending interrupts. If a semaphore associated has been registered, the ISR increments the semaphore value.

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

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Member Data Documentation

unsigned int MityDSP::tcDspPwm::mnInterruptCount

ISR counter (useful for debug).

SEM_Handle* MityDSP::tcDspPwm::mpMySemaphore [protected]

Pointer to registered semaphores.

volatile unsigned int* MityDSP::tcDspPwm::mpMyBaseReg [protected]

PWM Core base register.

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

PWM Core interrupt mask.

int MityDSP::tcDspPwm::mnMyIntLevel [protected]

PWM Core interrupt level.

int MityDSP::tcDspPwm::mnMyIntVector [protected]

PWM Core interrupt vector.

const int MityDSP::tcDspPwm::gnVerOffset = 0 [static, protected]

Version Register Offset.

const int MityDSP::tcDspPwm::gnCsrOffset = 1 [static, protected]

Control / Status Register Offset.

const int MityDSP::tcDspPwm::gnCdrOffset = 2 [static, protected]

Cycle Duration Register Offset.

const int MityDSP::tcDspPwm::gnPulseOffset = 3 [static, protected]

offset to first pulse register

const int MityDSP::tcDspPwm::gnPulseSize = 3 [static, protected]

num registers per pulse

const int MityDSP::tcDspPwm::gnDROffset = 0 [static, protected]

offset to DR from PulseOffset

const int MityDSP::tcDspPwm::gnCROffset = 1 [static, protected]

offset to DR from PulseOffset

const int MityDSP::tcDspPwm::gnPROffset = 2 [static, protected]

offset to DR from PulseOffset