Nexus Output

Nexus files are written by the NexusWriter. This Tango server is configured with an XML string (aka configuration) which is created by the NexusConfigurationServer, a Tango server. The configuration includes all selected components. A component specifies how data are stored in the Nexus file. The command AvailableComponents displays the list of available components. Components are selected from the Online command line, e.g.:

set write_nexus on
* = nexus_add_component( pilatus300k, default)
* = nexus_add_component( slit1, slit2, slit3, slit4)

After these commands are issued Nexus files are created after each scan.

Before the Nexus file is created Online does the following checks:

• Online assures that all user-selected components are in the list AvailableComponents.

• Online reads the MandatoryComponents and assure that they are in the list of user-selected components.

• Online compares the list of selected devices (scan device selection) with the list of data sources of the selected components. If a device does not appear in the data sources list, a dynamic component is created that allocates space for this device.

Components have be be prepared with a special designer.