# :INSTrument Subsystem

:INSTrument Commands

- :INSTrument Subsystem
- :INSTrument Connection Commands
- :INSTrument Simulated Commands

The connections subsystem assigns connections to oscilloscopes and virtual instruments. Eight instruments are available, with the first instrument reserved for the real-time oscilloscope, if present. Instruments can be occupied by any of the following connections:

- The real-time oscilloscope. The real-time oscilloscope is always assigned to instrument 1, if connected. If Infiniium is running on a PC, a connected oscilloscope can be removed and the instruments reassigned to hardware or simulated instruments.
- Simulated instruments

Connections 1 through 8 (2 through 8 when Infiniium is connected to a real-time oscilloscope) can be assigned to simulated instruments or supported external instruments. Use the `:INSTrument:CONNection:SELection` command to make assignments of an connection to an instrument. Once an connection is assigned to a channel, except for the oscilloscope, use the other commands in this subsystem to establish a communication connection between Infiniium and the instrument.

If you install a simulated instrument, use the commands in the `:SOURce Subsystem` subsystem to configure the instrument's simulated waveform.

The connection configuration settings are always saved with an instrument state file (`:DISK:SETup:SAVE` command). When opening an instrument state file with the `:DISK:SETup:RECall` command, use the `:DISK:SETup:RECall:ICONnection` command to select whether to import the connection configuration settings.