raw_data_1/selog

This has an NX_class of IXselog; this is not a class specified by upstream NeXus definitions. Each block is a group with an NX_class of IXseblock, which is also not a standard NeXus class.

The list of blocks to be written is defined by the IBEX configuration, and is user-editable in IBEX.

In addition to the list of blocks from IBEX, the following logs are written:

  • EPICS_PUTLOG: a string log containing the EPICS channel access put log, with each put operation as a string.

  • ICP_DAE_TD: This describes the difference between the DAE’s internal clock and a monotonic software clock

  • IDP_SYS_TD: This describes the difference between the monotonic software clock and an (NTP-corrected) system clock

Each IXseblock contains the following datasets:

raw_data_1/selog/<name>/vi_name

Under IBEX, this is always written as an empty string. It was previously used to refer to the filepath of a LabVIEW VI responsible for serving this data.

raw_data_1/selog/<name>/read_control

Under IBEX, this is always written as an empty string. It was previously used to refer to the path to this data within a LabVIEW VI.

raw_data_1/selog/<name>/set_control

Under IBEX, this is always written as an empty string. It was previously used to refer to the path to this data within a LabVIEW VI.

raw_data_1/selog/<name>/value

The latest value of the block in each period, as an array. This is written with a datatype corresponding to the underlying EPICS type.

For example, the array [12.34, 56.78] means that the most recent value while the instrument was in period 1 was 12.34, and the most recent value while the instrument was in period 2 was 56.78

Attributes:

  • units: Engineering units of the block, as per EPICS .EGU field.

raw_data_1/selog/<name>/value_spread

The difference between the minimum recorded value and maximum recorded value for a block in each period, as an array. This dataset is only written if the underlying EPICS type is numeric.

For example, the array [1.23, 0] means that:

  • The difference between the min and max values recorded while the instrument was in period 1 was 1.23

  • The difference between the min and max values recorded while the instrument was in period 2 was zero.

Attributes:

  • units: Engineering units of the block, as per EPICS .EGU field.

raw_data_1/selog/<name>/setpoint

The latest setpoint value of a block in each period, as an array. This is written with a datatype corresponding to the underlying EPICS type.

Attributes:

  • units: Engineering units of the block, as per EPICS .EGU field.

raw_data_1/selog/<name>/setpoint_spread

The difference between the minimum recorded value and maximum setpoint values for a block in each period, as an array. This dataset is only written if the underlying EPICS type is numeric.

Attributes:

  • units: Engineering units of the block, as per EPICS .EGU field.

The selog group also contains the following groups: