tomoStreamApp EPICS application

tomostream includes a complete example EPICS application, including:

• A database file and corresponding autosave request file that contain only the PVs required by the tomoscan.py base class.

• Database files and corresponding autosave request files that contain PVs used by the derived classes.

• An example IOC application that can be used to run the above databases. The databases are loaded in the IOC with the example substitutions file, tomoStream.substitutions.

Base class files

The following tables list all of the records in the tomoScan.template file. These records are used by the tomoscan base class and so are required.

tomoStream.template

This is the database file that contains only the PVs required by the tomoscan.py base class tomoStream.template.

tomoStream PV Prefixes

Record name	Record type	Description
$(P)$(R)TomoScanPVPrefix	stringout	Contains the prefix for the tomoscan controlling the data collection, e.g. 2bma:TomoScan

tomoStream PVA Names

Record name	Record type	Description
$(P)$(R)ImagePVAPName	stringout	Contains the name of the TomoScan PV storing the PV prefix of the images streamed by the detector
$(P)$(R)DarkPVAName	stringout	Contains the name of the TomoScan PVA where the dark images are stored
$(P)$(R)FlatPVAName	stringout	Contains the name of the TomoScan PVA where the flat images are stored
$(P)$(R)ThetaPVAName	stringout	Contains the name of the TomoScan PVA where the rotation angle positions are stored
$(P)$(R)ReconPVAName	stringout	Contains the name of the TomoStream PVA where the the selected 3 orthogonal slices are stored

Streaming analysis control

Record name	Record type	Description
$(P)$(R)CameraPVPrefix	stringout	Contains the prefix for the camera, e.g. 13BMDPG1:
$(P)$(R)Status	bo	Flag storing the streaming status. Choices are ‘Off’ and ‘On’. When ‘On’ the streaming reconstruction is enabled
$(P)$(R)BufferSize	longout	Stream buffer size
$(P)$(R)Center	ao	Rotation center for streaming reconstruction
$(P)$(R)FilterType	mbbo	Filter type for streaming reconstruction, ‘Parzen’, ‘Shepp-logan’, ‘Ramp’, ‘Butterworth’
$(P)$(R)OrthoX	longout	Ortho slice in the X direction for streaming reconstruction
$(P)$(R)OrthoY	longout	Ortho slice in the Y direction for streaming reconstruction
$(P)$(R)OrthoZ	longout	Ortho slice in the Z direction for streaming reconstruction

Stream status via Channel Access

Record name	Record type	Description
$(P)$(R)ReconStatus	waveform	This record will be updated with the stream reconstruction status while scanning.
$(P)$(R)ReconTime	ao	This record will update with the time to reconstruct the selected 3 orthogonal slices.
$(P)$(R)ServerRunning	bi	This record will be Running if the Python server is running and Stopped if not. It is controlled by a watchdog timer, and will change from Running to Stopped within 5 seconds if the Python server exits.

tomoStream_settings.req

This is the autosave request file for tomoStream.template tomoStream_settings.req.

It has the same usage and type of content as tomoStream_settings.req described above, except that it contains the PVs for the derived class TomoStream.

medm files

To start the tomostream medm screen:

$ cd /local/USERNAME/epics/synApps/support/tomostream/iocBoot/iocTomoStream
$ start_medm

where USERNAME is the username under which the tomoStreamApp is installed.

tomoStream.adl

The following is the MEDM screen tomoStream.adl. This screen contains the PVs to control tomoStream.

tomoStreamEPICS_PVs.adl

The EPICS PV names screen is below: