Detailed Description

template<typename T>
class nds::DataAcquisition< T >

This is a node that supplies a data acquisition PV and few control PV that specifies how the acquisition should be performed.

It also provides a state machine that allows to start/stop the acquisition.

The user of a DataAcquisition class must declare few delegate functions that specify the actions to perform when the acquisition node's state changes.

In particular, the transition from the state off to running should launch the data acquisition thread which pushes the acquired data via pushData(), while the transition from running to on should stop the data acquisition thread.

Template Parameters

T	the PV data type. The following data types are supported: std::int32_t std::double std::vector<std::int8_t> std::vector<std::uint8_t> std::vector<std::int32_t> std::vector<double> std::string

Examples:: oscilloscope/oscilloscope.cpp, and oscilloscopeMultiChannel/oscilloscopeMultiChannel.cpp.

#include <dataAcquisition.h>

Inheritance diagram for nds::DataAcquisition< T >:

Public Member Functions
	DataAcquisition ()
	Initializes an empty data acquisition node. More...

	DataAcquisition (const DataAcquisition< T > &right)
	Copies a data acquisition reference from another object. More...

	DataAcquisition (const std::string &name, size_t maxElements, stateChange_t switchOnFunction, stateChange_t switchOffFunction, stateChange_t startFunction, stateChange_t stopFunction, stateChange_t recoverFunction, allowChange_t allowStateChangeFunction)
	Constructs the data acquisition node. More...

void	setStartTimestampDelegate (getTimestampPlugin_t timestampDelegate)
	Set the function that retrieves the exaxt start time when the data acquisition starts. More...

void	push (const timespec &timestamp, const T &data)
	Push acquired data to the control system. More...

double	getFrequencyHz ()
	Retrieve the desidered acquisition frequency, in Hertz. More...

double	getDurationSeconds ()
	Retrieve the desidered duration of the acquisition, in seconds. More...

double	getAmplitude ()
	Retrieve the amplitude for the acquisition. More...

double	getOffset ()
	Retrieve the offset for the acquisition. More...

size_t	getMaxElements ()
	Retrieve the maximum number of elements that can be stored in the pushed array. This number is set in the DataAcquisition constructor. More...

size_t	getDecimation ()
	Retrieve the desidered decimation value. More...

size_t	getSamplingMode ()
	Retrieve the desidered sampling mode value. More...

size_t	getGround ()
	Retrieve the desidered ground state value. More...

timespec	getStartTimestamp () const
	Returns the timestamp at the moment of the start of the acquisition. More...

Public Member Functions inherited from nds::Node
	Node (const std::string &name, const nodeType_t nodeType=nodeType_t::generic)
	Construct the node. More...

template<class T >
T	addChild (T child)
	Add a child node or record to this node. This node will take ownership of the added one and will take care of deleting it. More...

void	initialize (void *pDeviceObject, Factory &factory)
	Registers all the records with the control system. Call this from the root node which will take care of traversing its children and initialize them. More...

Public Member Functions inherited from nds::Base
	Base (const Base &right)
	Copy constructor. The copy will refer to the same implementation object referenced in the copied object. More...

Base &	operator= (const Base &right)
	Copy operator. The copy will refer to the same implementation object referenced in the copied object. More...

void	setExternalName (const std::string &externalName)
	Set the string to pass to the naming rules in order to build the full node name as seen by the control system. More...

virtual Port	getPort ()
	Get the Node that communicate with the device (ASYN port on EPICS, Device on Tango). Query the parent nodes if necessary. More...

const std::string &	getComponentName () const
	Return the node's name. More...

const std::string &	getFullName () const
	Return the full node's name, prepending the parents' names if necessary (e.g. "ROOT-CHANNEL1-THISNODE") More...

const std::string &	getFullExternalName () const
	Return the full node's name as seen by the control system clients. More...

const std::string &	getFullNameFromPort () const
	Return the node's name as seen by the parent Port node (the node that communicates with the device). More...

timespec	getTimestamp () const
	Get the current time. More...

void	setTimestampDelegate (getTimestampPlugin_t timestampDelegate)
	Specify the delegate function to call to get the timestamp. More...

std::ostream &	getLogger (const logLevel_t logLevel)
	Retrieve a logging stream for the specified log level. More...

bool	isLogLevelEnabled (const logLevel_t logLevel) const
	Returns true if the logging for a particular severity level has been enabled. More...

void	setLogLevel (const logLevel_t logLevel)
	Enable the logging for a particular severity level. More...

void	defineCommand (const std::string &command, const std::string &usage, const size_t numParameters, const command_t function)
	Define a command specific for the node. More...

Thread	runInThread (const std::string &name, threadFunction_t function)
	Create and run a thread using the control system facilities. More...

Thread	runInThread (threadFunction_t function)
	Create and run a thread using the control system facilities. The created thread will have the node's name. More...

Additional Inherited Members
Protected Member Functions inherited from nds::Base
	Base ()
	Initializes an empty base class.

Constructor & Destructor Documentation

template<typename T>

nds::DataAcquisition< T >::DataAcquisition ( )

Initializes an empty data acquisition node.

You must assign a valid DataAcquisition node before calling initialize().

template<typename T>

nds::DataAcquisition< T >::DataAcquisition ( const DataAcquisition< T > & right )

Copies a data acquisition reference from another object.

Parameters

right a data acquisition holder from which the reference to the acquisition object implementation is copied

template<typename T>

nds::DataAcquisition< T >::DataAcquisition	(	const std::string &	name,
		size_t	maxElements,
		stateChange_t	switchOnFunction,
		stateChange_t	switchOffFunction,
		stateChange_t	startFunction,
		stateChange_t	stopFunction,
		stateChange_t	recoverFunction,
		allowChange_t	allowStateChangeFunction
	)

Constructs the data acquisition node.

Parameters

name	The node's name
maxElements	Maximum size of the acquired array. Set to 1 for scalar values
switchOnFunction	Delegate function that performs the actions to switch the node on
switchOffFunction	Delegate function that performs the actions to switch the node off
startFunction	Delegate function that performs the actions to start the acquisition (usually launches the acquisition thread)
stopFunction	Delegate function that performs the actions to stop the acquisition (usually stops the acquisition thread)
recoverFunction	Delegate function to execute to recover from an error state
allowStateChangeFunction	Delegate function that can deny a state change. Usually just returns true

Member Function Documentation

template<typename T>

double nds::DataAcquisition< T >::getAmplitude ( )

Retrieve the amplitude for the acquisition.

Returns: the amplitude for the acquisition

template<typename T>

size_t nds::DataAcquisition< T >::getDecimation ( )

Retrieve the desidered decimation value.

Returns: the decimation value

template<typename T>

double nds::DataAcquisition< T >::getDurationSeconds ( )

Retrieve the desidered duration of the acquisition, in seconds.

Returns: the desidered duration of the acquisition, in seconds

template<typename T>

double nds::DataAcquisition< T >::getFrequencyHz ( )

Retrieve the desidered acquisition frequency, in Hertz.

Returns: the acquisition frequency in Hertz

template<typename T>

size_t nds::DataAcquisition< T >::getGround ( )

Retrieve the desidered ground state value.

Returns: the ground state value

template<typename T>

size_t nds::DataAcquisition< T >::getMaxElements ( )

Retrieve the maximum number of elements that can be stored in the pushed array. This number is set in the DataAcquisition constructor.

Returns: the maximum number of elements that can be stored in the pushed array

template<typename T>

double nds::DataAcquisition< T >::getOffset ( )

Retrieve the offset for the acquisition.

Returns: the offset for the acquisition

template<typename T>

size_t nds::DataAcquisition< T >::getSamplingMode ( )

Retrieve the desidered sampling mode value.

Returns: the sampling mode value

template<typename T>

timespec nds::DataAcquisition< T >::getStartTimestamp ( ) const

Returns the timestamp at the moment of the start of the acquisition.

This value is set by the state machine when the state switches to running. If a timing plugin is active then the timestamp is taken from the plugin.

Returns: the time when the acquisition started.

template<typename T>

void nds::DataAcquisition< T >::setStartTimestampDelegate ( getTimestampPlugin_t timestampDelegate )

Set the function that retrieves the exaxt start time when the data acquisition starts.

Parameters

timestampDelegate the function that returns the exact starting time of the data acquisition

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

/home/travis/build/Cosylab/nds3/include/nds3/dataAcquisition.h

Detailed Description

template<typename T> class nds::DataAcquisition< T >

Public Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

Member Function Documentation

template<typename T>
class nds::DataAcquisition< T >