SCPI commands follow a tree-like structure, 
organized into nodes. Each level of the 
command tree is a node. Each keyword in an 
SCPI command represents each node in the 
command tree. Each keyword (node) of an SCPI 
command is separated by a colon (:). 
For example, the diagram below shows an SCPI 
sub-structure and a command example.  
There are a number of different instrument 
commands and queries. A command sends 
instructions or data to the unit and a query 
receives data or status information from the 
unit.