pflib::packing::TriggerLinkFrame Struct Reference

Without a trigger link set up, the decoding cannot be fuctionally tested. More...

#include <TriggerLinkFrame.h>

Collaboration diagram for pflib::packing::TriggerLinkFrame:

Public Member Functions
uint8_t	compressed_sum (int i_sum, int i_bx=0) const
	Get a specific compressed trigger sum from the data words.
uint32_t	linearized_sum (int i_sum, int i_bx=0) const
	Get a specific linearized trigger sum from the data words.
void	from (std::span< uint32_t > data)
	Parse into this link frame from a std::span over 32-bit words.
	TriggerLinkFrame (std::span< uint32_t > data)
	Construct from a std::span over 32-bit words.
	TriggerLinkFrame ()=default
	default constructor which does nothing

Static Public Member Functions
static uint32_t	compressed_to_linearized (uint8_t cs)
	Convert a compressed trigger sum into its linearized equivalent.

Public Attributes
int	i_link
	trigger link identification number
std::array< uint32_t, 4 >	data_words
	Trigger words including one pre-sample and 2 following samples.
std::array< bool, 5 >	corruption
	Checks on data format.
logging::logger	the_log_ {logging::get("decoding")}
	handle to logging for decoding warnings

Static Public Attributes
static const int	i_soi_ = 1
	index of data words containg sample of interest

Detailed Description

Without a trigger link set up, the decoding cannot be fuctionally tested.

This class is merely a skeleton of how unpacking could be done for these trigger link frames on a fiberless setup. This class does not handle the change in format the happens when the trigger data streams from one or more ROCs are processed by an ECON-T.

Constructor & Destructor Documentation

TriggerLinkFrame()

pflib::packing::TriggerLinkFrame::TriggerLinkFrame

(

std::span< uint32_t >

data

)

Construct from a std::span over 32-bit words.

Note

A std::span can be transparently constructed from a std::vector if that is what is available, but it can also be used to simply view a subslice of a larger std::vector.

Member Function Documentation

compressed_sum()

uint8_t pflib::packing::TriggerLinkFrame::compressed_sum	(	int	i_sum,
		int	i_bx = 0 ) const

Get a specific compressed trigger sum from the data words.

Parameters

[in]	i_sum	sum index 0, 1, 2, or 3
[in]	i_bx	bunch index relative to i_soi_ -1, 0, 1, or 2

Returns

compressed trigger sum as determined by the chip

compressed_to_linearized()

uint32_t pflib::packing::TriggerLinkFrame::compressed_to_linearized ( uint8_t cs )

static

Convert a compressed trigger sum into its linearized equivalent.

The chip lossy compresses its trigger sums into seven bits using the 4E+3M encoding and this function decompresses the sum into our best estimate of what the on-chip trigger sum was.

Note

This function undoes the wacky compression algorithm, but the scale of the linearized sum is not quite correct. If SelTC4 = 1 on the chip (sums of 4 channels), then this result needs to be multiplied by 2 (or left-bit-shift by one). If SelTC4 = 0 on the chip (sums of 9 channels), then this result needs to be multiplied by 8 (or left-bit-shift by three)

If SelTC4 stores the setting on the chip when the data was collected and lin_val is the value returned by this function, then

lin_val << (SelTC4 ? 1 : 3)

is the integer value pertaining to the correct scale of the sums as determined on the chip.

Parameters

[in]

cs

compressed sum to unpack

Returns

unpacked linearized sum

linearized_sum()

uint32_t pflib::packing::TriggerLinkFrame::linearized_sum	(	int	i_sum,
		int	i_bx = 0 ) const

Get a specific linearized trigger sum from the data words.

See also

compressed_sum for how accessing a specific sum within a trigger word is implemented.

compressed_to_linearized for how this compressed seven-bit sum is unpacked into the linearized form.

Parameters

[in]	i_sum	sum index 0, 1, 2, or 3
[in]	i_bx	bunch index relative to i_soi_ -1, 0, 1, or 2

Returns

linearized trigger sum as determined by the chip

Member Data Documentation

corruption

std::array<bool, 5> pflib::packing::TriggerLinkFrame::corruption

Checks on data format.

Index	Description
0	leading four-bits of sw header is wrong
1	leading four-bits of 0'th data word is wrong
2	leading four-bits of 1st data word is wrong
3	leading four-bits of 2nd data word is wrong
4	leading four-bits of 3rd data word is wrong

data_words

std::array<uint32_t, 4> pflib::packing::TriggerLinkFrame::data_words

Trigger words including one pre-sample and 2 following samples.

A trigger word contains 4 7-bit trigger sums and a 4-bit leading header to help check for corruption and link alignment.

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

• include/pflib/packing/TriggerLinkFrame.h
• src/pflib/packing/TriggerLinkFrame.cxx