An Epics Instrument is simply a grouping of low-level parameters (Process Variables) as exposed through Epics Channel Access. At first, this may not seem very interesting. However, Epics Instruments allows you to
The Epics Instruments application allows you to group these components into a logical group -- an Instrument. Once an Instrument has been defined, you can then save and restore settings for this Instrument. Furthermore, these settings are automatcally saved in a single, portable file for later use.
Epics Channel Access gives a simple and robust interface to its lowest common unit -- the Process Variable or PV. The Epics control system also provides sophisticated ways to express and manipulate complex devices, both physical and virtual. Creating such devices and defining their behavior is generally done by well-trained programmers. The application here uses a much simpler approach that can expose some categories of "Settings" that may need to changed en masse, and returned to at a later time.
As defined here, An Epics Instrument is simply a named collection of Epics Process Variables (PVs). The PVs do not need to be physically related to one another nor be associated with a single Epics Record or Device. Rather, an Instrument is defined at the level of the Epics Channel Access client, allowing a station scientist or engineer to use their own grouping of PVs as an abstract "Instrument". A simple example would be a pair of motors that work together to move some device.
In addition to a name and a set of PVs, an Instrument has a set of "named Positions". At any point, the current values of an Instruments PVs can be saved as its Position. And, of course, the named Positions can then be restored simply by selecting the Position.