QCrateReceiverBuffer Class Reference

List of all members.

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Detailed Description

class for shared memory handling

Author:

sergio.didomizio@ge.infn.it

One object of this kind will handle a shared memory structure for a single DAQ channel.
Shared memory structure contains some useful variables and a data buffer containing one long word for each acquired sample.
See QBufferStructure_t documentation below for further details about content of shared memory structure.
Follows a description of the format of a single word in data buffer.

• Informations contained in a single long word (32 bit) are:
  • 18 bit signed value returned by ADC
  • 4 bit for 4 independent trigger flags
  • 4 bit counter, mainly needed for debugging phase and used to check that there is no data loss
  • 2 bit fot trigger enable/disable flag
  • 4 remaining bits are unused

• Bit structure is:
  • bits 0-16 and bit 31: ADC sample formatted in two's complement (bit 31 is the sign). See http://en.wikipedia.org/wiki/Two's_complement for description of two's complement format.
  • bits 17-20 the 4 trigger flags
  • bits 21-24 the 4 bit counter
  • bits 25-26 trigger enable/disable flags
  • bits 27-30 unused

Public Member Functions
	QCrateReceiverBuffer (unsigned long ch, bool attach, bool OpenFiles, int RunNumber=0, bool offset_shm=false)
unsigned long	Size () const
char *	Start () const
	get pointer to first valid word
unsigned long	GetNumberOfWords () const
	get number of valid words in buffer
bool	EnableTriggerPointer ()
	book trigger pointer
void	ReleaseTriggerPointer ()
	release trigger pointer (do nothing if it wasn't booked)
bool	EnableBuilderPointer ()
	book builder pointer
void	ReleaseBuilderPointer ()
	release builder pointer (do nothing if it wasn't booked)
bool	EnableReadPointer ()
	book read pointer
void	ReleaseReadPointer ()
	release read pointer (do nothing if it wasn't booked)
void	Release (unsigned int n)
	remove data from circular buffer
void	Add (int n, const long *data)
	add data to circular buffer
void	AddFromNetwork (QConnectedSocket *cs)
	get data from network and add to buffer
int	GetLg () const
	get logical channel
int	ReadToEnd () const
	distance of read pointer to end of buffer
void	SetProcessed (unsigned int n)
	flag n words as processed by trigger
void	SetBuilt (unsigned int n)
	flag n words as processed by builder
unsigned long	GetToBeProcessed () const
unsigned long	GetToBeBuilt () const
	number of valid words still to be processed by builder
unsigned long	GetToBeRead () const
	number of valid words still to be read
unsigned long long	GetProcessed () const
	get pointer to the first word still to be processed by trigger
unsigned long long	GetBuilt () const
	get pointer to the first word to be processed by builder
unsigned long long	GetRead () const
	get pointer to the first word to be read
unsigned long long	GetWritten () const
	get pointer to the first free word in buffer
long	GetData (unsigned long long index) const
	get data
long	GetSample (unsigned long long index) const
	get sample
short	GetTriggerFlags (unsigned long long index, unsigned long mask=0xF) const
	get trigger flags for given sample
void	FlagTrigger (unsigned long long index, int tag)
	flag word with trigger tag
void	SetTriggerEnabled (bool enabled)
	set trigger enable/disable flag
void	SetSamplingRate (unsigned long rate)
	set sampling rate
unsigned long	GetSamplingRate () const
	get sampling rate
long long	GetTimeOfSample (unsigned long long index) const
	get time associated to a given sample index
unsigned long long	GetSampleOfTime (long long time) const
	get sample index associated to a given time
void	Dump ()
void	SetScanned (unsigned long long i)
void	SetAnalyzed (unsigned long long i)
Private Member Functions
void	Release ()
void	SetProcessed ()
	private method used to update trigger pointer when it is not booked
void	SetBuilt ()
	private method used to update builder pointer when it is not booked
unsigned long	GetToBeWritten () const
	get number of words still to be written on gzipped file
void	WriteFile ()
	write data in gzipped file
void	OpenFile ()
	open new gzipped file
void	CloseFile (bool last)
	close current gzipped file
Private Attributes
int	fHandle
int	fShmid
bool	fOwn
QBufferStructure_t *	p_buffer
gzFile	zFile
std::string	fGzFileName
unsigned int	fPartialFile
bool	fReadPtrBooked
bool	fBuilderPtrBooked
bool	fTrgPtrBooked

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Member Function Documentation

bool QCrateReceiverBuffer::EnableTriggerPointer

(

)

book trigger pointer

For each shared memory, only one instance of QCrateReceiverBuffer can take control of trigger pointer

Returns:

true if booking succeeded, false otherwise

bool QCrateReceiverBuffer::EnableBuilderPointer

(

)

book builder pointer

For each shared memory, only one instance of QCrateReceiverBuffer can take control of builder pointer

Returns:

true if booking succeeded, false otherwise

bool QCrateReceiverBuffer::EnableReadPointer

(

)

book read pointer

For each shared memory, only one instance of QCrateReceiverBuffer can take control of read pointer

Returns:

true if booking succeeded, false otherwise

void QCrateReceiverBuffer::Release

(

unsigned int

n

)

[inline]

remove data from circular buffer

Parameters:

n

number of samples to be removed

void QCrateReceiverBuffer::Add	(	int	n,
		const long *	data
	)

add data to circular buffer

Parameters:

	n	number of words to be added
	data	pointer to buffer containing data

long QCrateReceiverBuffer::GetData

(

unsigned long long

index

)

const [inline]

get data

By "data" we mean the complete content of the long word identified by index. Use GetSample method if you're intereste only to the part of long word containing value sampled by ADC (see the top of this file for detailed descripion of data structure).

Parameters:

index

index of data to be returned

long QCrateReceiverBuffer::GetSample

(

unsigned long long

index

)

const [inline]

get sample

return the value sampled by ADC identified by index. It is not the whole content of the long word contained in the buffer, but a subpart of it. See the top of this file for detailed description of data sctructure.

Parameters:

index

index of sample to be returned

short QCrateReceiverBuffer::GetTriggerFlags	(	unsigned long long	index,
		unsigned long	mask = 0xF
	)			const [inline]

get trigger flags for given sample

Parameters:

	index	index of sample for which trigger flags are returned
	mask	bit mask that can be used to return only a subset of the trigger flags. Defaults to all (0xF).

Returns:

short containing the 4 trigger flags in the 4 LSB bits.

void QCrateReceiverBuffer::FlagTrigger	(	unsigned long long	index,
		int	tag
	)			[inline]

flag word with trigger tag

documentation to be added

void QCrateReceiverBuffer::SetTriggerEnabled

(

bool

enabled

)

[inline]

set trigger enable/disable flag

When this method is called, a flag is set in last sample written by Daq.

Parameters:

enabled

if true, bit 26 is flagged. If false, bit 25 is flagged

long long QCrateReceiverBuffer::GetTimeOfSample

(

unsigned long long

index

)

const [inline]

get time associated to a given sample index

Parameters:

index

sample index for which time is requested

Returns:

time associated to the requested index; if index do not fall between the first and the last valid index (i.e. that sample is not available) a negative time is returned

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Member Data Documentation

int QCrateReceiverBuffer::fShmid [private]

shared memory id

bool QCrateReceiverBuffer::fOwn [private]

true if shared memory is owned by this instance of QCrateReceiverBuffer

QBufferStructure_t* QCrateReceiverBuffer::p_buffer [private]

pointer to shared memory buffer

gzFile QCrateReceiverBuffer::zFile [private]

pointer to single channel data file

std::string QCrateReceiverBuffer::fGzFileName [private]

single channel data file name

unsigned int QCrateReceiverBuffer::fPartialFile [private]

partial file number

bool QCrateReceiverBuffer::fReadPtrBooked [private]

true if this instance of QCrateReceiver has control on read ptr

bool QCrateReceiverBuffer::fBuilderPtrBooked [private]

true if this instance of QCrateReceiverBuffer has control on builder pointer

bool QCrateReceiverBuffer::fTrgPtrBooked [private]

true if this instance of QCrateReceiverBuffer has control on trigger pointer

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

• /usr/local/cuore/pkg/comm/QCrateReceiverBuffer.hh
• /usr/local/cuore/pkg/comm/QCrateReceiverBuffer.cc

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