The control system is made up of devices. Examples of devices are Faraday cups, charging voltage supplies, bending magnets, and electrostatic quads.
A device is identified by what is called the Label. It is 8 characters long. By convention the label is usually (not always) made of three fields.
The first field is the device name and is 3 characters long. The device name is to be right padded with spaces if less than 3 characters are needed.
Examples:
Faraday Cup
Electrostatic Quad
Focus Power Supply
Terminal Potential Stabilizer
The second field describes a region on the beamline.
Examples:
First ion source
Preacceleration beamline
Tank entrance area (usually refers to items in the tank)
Tank exit area (usually refers to items in the tank)
The third field is a serial number. It describes an occurance of a device in a region on the beamline.
A complete Label looks like this:
First Faraday cup on the preacceleration beamline
Second Faraday cup on the preacceleration beamline
First preacceleration beamline magnet
Post acceleration electrostatic quad (inside tank at exit end)
There are exceptions to this naming convention. For example, the label "SETUP" has as its parameters all of the particle related information such as total machine energy, species, charge state, etc.
A device is made up of a set of parameters. Parameters are considered single control and readback points. These parameters are identified by what is called a tag name. A tag name is a combination of the device label and a RefName.
Example RefNames (typical of a Faraday cup):
Position Status Control
Position Status Read
Cup Current Read
The complete tags for the parameters associated with first preacceleration Faraday cup are:
Position Status Control
Position Status Read
Cup current read