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.

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 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.

---

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

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