Overview
The CSS EPICS PV Tree displays the hierarchical data flow between EPICS
records.
It displays the record types, their current values as well as
severity/status.
It attempts to follow the data flow by traversing input links
(INP, INPA, DOL, ...).
Usage
Enter a name into the "PV" text box, and see what happens.
Names can be entered in various ways:
- Type a PV name, followed by "Return".
- Select a previously entered PV name from the drop-down list
attached to the PV name text box.
- Drop a PV name from another CSS application into the "Tree" area
below the PV name.
- Send a PV name to the EPICS PV tree via the context menu of another
CSS application.
Examples
The first screenshot shows an analog input (ai) record, which reads its
input (INP) directly from a device support module that happens to understand
the input description "adm606m....".
The second screenshot shows a more interesting hierarchy:
A binary input record (bi) reads from a calculation (calc), whose first input
(INPA) reads from an mbbi which in turn reads from another calc and so on.
Note how the color-coding indicates severities.
Limitations
This tool uses the EPICS network protocol, Channel Access, to read PVs.
Since there is no way to query EPICS V3 IOCs for their database information,
the knowledge of record types as well as their input links is hard-coded
into the application. It will not handle record types outside of EPICS 'base',
and it might not even fully handle all record types inside EPICS 'base'.