About Commands
PCR-WE Interface Manual
51
About Commands
The information that is transferred between the controller (PC) and the device (PCR-
WE/WE2 series) is referred to as messages.
This product uses the SCPI language for these messages.
The messages that the PC sends to the product are commands. The messages that
the product sends to the PC are responses.
Command Hierarchy
SCPI is an ASCII-based command language that was designed for test and measur-
ing equipment. The command structure is composed of the common roots and nodes
that are the building blocks of the SCPI subsystem. A command consists of a pro-
gram header, parameters, and punctuation marks.
The following table uses the SOURce subsystem as an example to explain the hier-
archy.
Program header
Parameter
Node level
SOUR:
Root node
FREQ
2nd level
:LIM
3rd level
:UPP
<numeric>
4th level
:LOW
<boolean>
4th level
VOLT
2nd level
:RANGE
3rd level
:UPP
<numeric>
4th level
:AUTO
<boolean>
4th level
A colon (:) separates a higher node from a lower node.