NDPluginDriver Class Reference

Class from which actual plugin drivers are derived; derived from asynNDArrayDriver. More...

#include <NDPluginDriver.h>

Inheritance diagram for NDPluginDriver:

asynNDArrayDriver asynPortDriver NDPluginColorConvert NDPluginFile NDPluginOverlay NDPluginProcess NDPluginROI NDPluginStats NDPluginStdArrays NDPluginTransform

List of all members.

Public Member Functions

 NDPluginDriver (const char *portName, int queueSize, int blockingCallbacks, const char *NDArrayPort, int NDArrayAddr, int maxAddr, int numParams, int maxBuffers, size_t maxMemory, int interfaceMask, int interruptMask, int asynFlags, int autoConnect, int priority, int stackSize)
 Constructor for NDPluginDriver; most parameters are simply passed to asynNDArrayDriver::asynNDArrayDriver.
virtual asynStatus writeInt32 (asynUser *pasynUser, epicsInt32 value)
 Called when asyn clients call pasynInt32->write().
virtual asynStatus writeOctet (asynUser *pasynUser, const char *value, size_t maxChars, size_t *nActual)
 Called when asyn clients call pasynOctet->write().
virtual asynStatus readInt32Array (asynUser *pasynUser, epicsInt32 *value, size_t nElements, size_t *nIn)
 Called when asyn clients call pasynInt32Array->read().
virtual void driverCallback (asynUser *pasynUser, void *genericPointer)
 Method that is called from the driver with a new NDArray.
virtual void processTask (void)
 Method runs as a separate thread, waiting for NDArrays to arrive in a message queue and processing them.

Protected Member Functions

virtual void processCallbacks (NDArray *pArray)
 Method that is normally called at the beginning of the processCallbacks method in derived classes.
virtual asynStatus connectToArrayPort (void)
 Connect this plugin to an NDArray port driver; disconnect from any existing driver first, register for callbacks if enabled.

Protected Attributes

asynUser * pasynUserGenericPointer
 asynUser for connecting to NDArray driver
void * asynGenericPointerPvt
 Handle for connecting to NDArray driver.
asynGenericPointer * pasynGenericPointer
 asyn interface for connecting to NDArray driver
int NDPluginDriverArrayPort
int NDPluginDriverArrayAddr
int NDPluginDriverPluginType
int NDPluginDriverDroppedArrays
int NDPluginDriverEnableCallbacks
int NDPluginDriverBlockingCallbacks
int NDPluginDriverMinCallbackTime


Detailed Description

Class from which actual plugin drivers are derived; derived from asynNDArrayDriver.

Constructor & Destructor Documentation

NDPluginDriver::NDPluginDriver ( const char *  portName,
int  queueSize,
int  blockingCallbacks,
const char *  NDArrayPort,
int  NDArrayAddr,
int  maxAddr,
int  numParams,
int  maxBuffers,
size_t  maxMemory,
int  interfaceMask,
int  interruptMask,
int  asynFlags,
int  autoConnect,
int  priority,
int  stackSize 
)

Constructor for NDPluginDriver; most parameters are simply passed to asynNDArrayDriver::asynNDArrayDriver.

After calling the base class constructor this method creates a thread to execute the NDArray callbacks, and sets reasonable default values for all of the parameters defined in NDPluginDriver.h.

Parameters:
[in] portName The name of the asyn port driver to be created.
[in] queueSize The number of NDArrays that the input queue for this plugin can hold when NDPluginDriverBlockingCallbacks=0. Larger queues can decrease the number of dropped arrays, at the expense of more NDArray buffers being allocated from the underlying driver's NDArrayPool.
[in] blockingCallbacks Initial setting for the NDPluginDriverBlockingCallbacks flag. 0=callbacks are queued and executed by the callback thread; 1 callbacks execute in the thread of the driver doing the callbacks.
[in] NDArrayPort Name of asyn port driver for initial source of NDArray callbacks.
[in] NDArrayAddr asyn port driver address for initial source of NDArray callbacks.
[in] maxAddr The maximum number of asyn addr addresses this driver supports. 1 is minimum.
[in] numParams The number of parameters that the derived class supports.
[in] maxBuffers The maximum number of NDArray buffers that the NDArrayPool for this driver is allowed to allocate. Set this to -1 to allow an unlimited number of buffers.
[in] maxMemory The maximum amount of memory that the NDArrayPool for this driver is allowed to allocate. Set this to -1 to allow an unlimited amount of memory.
[in] interfaceMask Bit mask defining the asyn interfaces that this driver supports.
[in] interruptMask Bit mask definining the asyn interfaces that can generate interrupts (callbacks)
[in] asynFlags Flags when creating the asyn port driver; includes ASYN_CANBLOCK and ASYN_MULTIDEVICE.
[in] autoConnect The autoConnect flag for the asyn port driver.
[in] priority The thread priority for the asyn port driver thread if ASYN_CANBLOCK is set in asynFlags.
[in] stackSize The stack size for the asyn port driver thread if ASYN_CANBLOCK is set in asynFlags.


Member Function Documentation

asynStatus NDPluginDriver::connectToArrayPort ( void   )  [protected, virtual]

Connect this plugin to an NDArray port driver; disconnect from any existing driver first, register for callbacks if enabled.

void NDPluginDriver::driverCallback ( asynUser *  pasynUser,
void *  genericPointer 
) [virtual]

Method that is called from the driver with a new NDArray.

It calls the processCallbacks function, which typically is implemented in the derived class. It can either do the callbacks directly (if NDPluginDriverBlockingCallbacks=1) or by queueing the arrays to be processed by a background task (if NDPluginDriverBlockingCallbacks=0). In the latter case arrays can be dropped if the queue is full. This method should really be private, but it must be called from a C-linkage callback function, so it must be public.

Parameters:
[in] pasynUser The pasynUser from the asyn client.
[in] genericPointer The pointer to the NDArray

void NDPluginDriver::processCallbacks ( NDArray pArray  )  [protected, virtual]

Method that is normally called at the beginning of the processCallbacks method in derived classes.

Parameters:
[in] pArray The NDArray from the callback.
This method takes care of some bookkeeping for callbacks, updating parameters from data in the class and in the NDArray. It does asynInt32Array callbacks for the dimensions array if the dimensions of the NDArray data have changed.

Reimplemented in NDPluginColorConvert, NDPluginFile, NDPluginOverlay, NDPluginProcess, NDPluginROI, NDPluginStats, NDPluginStdArrays, and NDPluginTransform.

void NDPluginDriver::processTask ( void   )  [virtual]

Method runs as a separate thread, waiting for NDArrays to arrive in a message queue and processing them.

This thread is used when NDPluginDriverBlockingCallbacks=0. This method should really be private, but it must be called from a C-linkage callback function, so it must be public.

asynStatus NDPluginDriver::readInt32Array ( asynUser *  pasynUser,
epicsInt32 *  value,
size_t  nElements,
size_t *  nIn 
) [virtual]

Called when asyn clients call pasynInt32Array->read().

Returns the value of the array dimensions for the last NDArray.

Parameters:
[in] pasynUser pasynUser structure that encodes the reason and address.
[in] value Pointer to the array to read.
[in] nElements Number of elements to read.
[out] nIn Number of elements actually read.

Reimplemented from asynPortDriver.

Reimplemented in NDPluginStdArrays.

asynStatus NDPluginDriver::writeInt32 ( asynUser *  pasynUser,
epicsInt32  value 
) [virtual]

Called when asyn clients call pasynInt32->write().

This function performs actions for some parameters, including NDPluginDriverEnableCallbacks and NDPluginDriverArrayAddr. For all parameters it sets the value in the parameter library and calls any registered callbacks..

Parameters:
[in] pasynUser pasynUser structure that encodes the reason and address.
[in] value Value to write.

Reimplemented from asynPortDriver.

Reimplemented in NDPluginFile, NDPluginStats, and NDPluginTransform.

asynStatus NDPluginDriver::writeOctet ( asynUser *  pasynUser,
const char *  value,
size_t  nChars,
size_t *  nActual 
) [virtual]

Called when asyn clients call pasynOctet->write().

This function performs actions for some parameters, including NDPluginDriverArrayPort. For all parameters it sets the value in the parameter library and calls any registered callbacks..

Parameters:
[in] pasynUser pasynUser structure that encodes the reason and address.
[in] value Address of the string to write.
[in] nChars Number of characters to write.
[out] nActual Number of characters actually written.

Reimplemented from asynNDArrayDriver.

Reimplemented in NDFileNexus.


Member Data Documentation

Handle for connecting to NDArray driver.

asynGenericPointer* NDPluginDriver::pasynGenericPointer [protected]

asyn interface for connecting to NDArray driver

asynUser for connecting to NDArray driver


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

Generated on Thu May 20 18:01:43 2010 for areaDetector by  doxygen 1.5.7.1