MityDSP::tcDspAwg Class Reference

Instances of this class handle configuring, and enabling the MityDSP Arbitrary Waveform Generator core I/O interface. More...

#include <core/DspAwg.h>

List of all members.

Classes
union	tuSampleData
	Definition of sample data holding area. More...

Public Types
enum	teDegOrRad { eeDegrees, eeRadians }
	Enumeration to specify inputs in degrees vs. radians. More...

Public Member Functions
	tcDspAwg (void *apAddress)
	This constructor is used to open a AWG core instance.
	~tcDspAwg ()
	Default destructor.
void	Enable (bool abEnable)
	Enable the AWG Core (output waveform on next clock if internally triggered, or next clock after external trigger).
void	SetExtTrigger (bool abExtTrigger)
	Configure AWG Trigger Mode.
void	SetPhase (unsigned int anPhase)
	Configure AWG starting phase.
void	SetPhase (double afValue, teDegOrRad aeUnits)
	Configure AWG starting phase.
void	SetPhaseIncrement (unsigned int anPhaseInc)
	Set the AWG phase increment.
void	SetPhaseIncrement (double afValue, teDegOrRad aeUnits)
	Set the AWG phase increment.
int	SetWaveformSamples (unsigned short *apValues, int anNumValues, int anStartIndex=0, bool abImplementNow=true)
	Update the working copy of the AWG waveform sample table.
void	SetWaveformSin (unsigned short anHalfAmplitude=0x7FFF)
	Configure AWG waveform memory for sin wave output.
bool	IsEnabled (void)
	Check if AWG Core is enabled.
bool	IsExtTriggered (void)
	Check if AWG Core is configured for external trigger operation.
unsigned int	GetPhase (void)
	Read back the current 24-bit phase value.
unsigned int	GetPhaseIncrement (void)
	Read back the current phase increment value.

Static Public Attributes
static const int	gnNumSamples = 512
	Number of waveform samples supported.
static const int	gnPhaseAccumulatorSize = 0x01000000
	Number of possible phase values.

Protected Member Functions
void	CopyWaveform (void)
	Internal routine to copy the working waveform table to the FPGA core.

Protected Attributes
SEM_Handle	mhMutex
volatile unsigned int *	mpBaseAddr
	Mutex to serialize access.
tuSampleData	maSamples [gnNumSamples]
	AWG Core base address.

---

Detailed Description

Instances of this class handle configuring, and enabling the MityDSP Arbitrary Waveform Generator core I/O interface.

Each AWG Core provides 512 16-bit samples (linearly interpolated) to define a waveform, and a 24-bit phase accumulator and programmable increment to define the frequency.

See also:

tcDspAwg Page

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Member Enumeration Documentation

enum MityDSP::tcDspAwg::teDegOrRad

Enumeration to specify inputs in degrees vs. radians.

Enumerator:

eeDegrees
eeRadians

---

Constructor & Destructor Documentation

tcDspAwg::tcDspAwg

(

void *

apAddress

)

This constructor is used to open a AWG core instance.

The base address of the FPGA core must be provided.

Parameters:

[in]

apAddress

The base address of the AWG core.

Returns:

None.

See also:

DspAwg.h

tcDspAwg::~tcDspAwg

(

)

Default destructor.

---

Member Function Documentation

void tcDspAwg::Enable

(

bool

abEnable

)

Enable the AWG Core (output waveform on next clock if internally triggered, or next clock after external trigger).

Parameters:

[in]

abEnable

When true, waveform generation is enabled.

Returns:

None.

void tcDspAwg::SetExtTrigger

(

bool

abExtTrigger

)

Configure AWG Trigger Mode.

Parameters:

[in]

abExtTrigger

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.

void tcDspAwg::SetPhase

(

unsigned int

anPhase

)

Configure AWG starting phase.

It is not recommended that this value be updated while the AWG is enabled.

Parameters:

[in]

anPhase

The initial phase, as a 24-bit integer.

Returns:

None.

void tcDspAwg::SetPhase	(	double	afValue,
		teDegOrRad	aeUnits
	)

Configure AWG starting phase.

It is not recommended that this value be updated while the AWG is enabled.

Parameters:

[in]	afValue	The initial phase, as double precision float.
[in]	aeUnits	Indicates whether phase is in degrees (eeDegrees) or radians (eeRadians)

Returns:

None.

void tcDspAwg::SetPhaseIncrement

(

unsigned int

anPhaseInc

)

Set the AWG phase increment.

This is the number of counts that the 24-bit phase register is incremented each clock cycle. The waveform value output is linearly interpolated from the surrounding values in the sample table.

Parameters:

[in]

anPhaseInc

The phase increment, as a 24-bit integer.

Returns:

None.

void tcDspAwg::SetPhaseIncrement	(	double	afValue,
		teDegOrRad	aeUnits
	)

Set the AWG phase increment.

This is the number of counts that the 24-bit phase register is incremented each clock cycle. The waveform value output is linearly interpolated from the surrounding values in the sample table.

Parameters:

[in]	afValue	The phase increment, as a 24-bit integer.
[in]	aeUnits	Indicates whether phase increment is in degrees (eeDegrees) or radians (eeRadians).

Returns:

None.

int tcDspAwg::SetWaveformSamples	(	unsigned short *	apValues,
		int	anNumValues,
		int	anStartIndex = 0,
		bool	abImplementNow = true
	)

Update the working copy of the AWG waveform sample table.

This table consists of 512 16-bit amplitude samples uniformly distributed across 360-degrees of phase. The number of samples to be provided, and (optionally) the starting index in the sample table are provided. A boolean indicates whether or not the working table should be loaded to the FPGA following the update.

Note:

The application need only provide the 512 16-bit samples. Offsetting and repeating the values as required for the FPGA is handled internally.

For a discontinuous waveform, 513 samples may be provided. The last data point becomes the "next" sample for the 512th entry in the waveform table. Discontinuous waveforms cannot be defined in sections.

Parameters:

[in]	apValues	Pointer to an array of 16-bit sample values.
[in]	anNumValues	Number of values provided (0-512).
[in]	anStartIndex	Starting index in the sample table (0-511, default:0).
[in]	abImplementNow	Indicates whether or not working table should be copied to AWG (default: true).

Returns:

Number of samples actually written.

void tcDspAwg::SetWaveformSin

(

unsigned short

anHalfAmplitude = 0x7FFF

)

Configure AWG waveform memory for sin wave output.

The output is scaled to be centered at 1/2 the full scale output of the AWG.

Parameters:

[in]

anHalfAmplitude

Number of LSB's for 1/2 amplitude. Maximum value should be 0x7FFF.

Returns:

None.

bool tcDspAwg::IsEnabled

(

void

)

Check if AWG Core is enabled.

Returns:

true if the core is enabled.

bool tcDspAwg::IsExtTriggered

(

void

)

Check if AWG Core is configured for external trigger operation.

Returns:

true if the core triggering is from external source.

unsigned int tcDspAwg::GetPhase

(

void

)

Read back the current 24-bit phase value.

Returns:

The 24-bit phase value.

unsigned int tcDspAwg::GetPhaseIncrement

(

void

)

Read back the current phase increment value.

Returns:

The current 24-bit phase increment per clock.

void tcDspAwg::CopyWaveform ( void  )

protected

Internal routine to copy the working waveform table to the FPGA core.

Note:

Currently, no support for a partial table load. The working table may be loaded in pieces, but sending the working table to the FPGA is always done in its entirety.

Returns:

None.

---

Member Data Documentation

const int MityDSP::tcDspAwg::gnNumSamples = 512

static

Number of waveform samples supported.

const int MityDSP::tcDspAwg::gnPhaseAccumulatorSize = 0x01000000

static

Number of possible phase values.

SEM_Handle MityDSP::tcDspAwg::mhMutex

protected

volatile unsigned int* MityDSP::tcDspAwg::mpBaseAddr

protected

Mutex to serialize access.

tuSampleData MityDSP::tcDspAwg::maSamples[gnNumSamples]

protected

AWG Core base address.