ITech IT7900 Series Programming Guide

SCPI Introduction
Copyright © ITECH Electronic Co., Ltd. 2
⚫ Head paths influence how the instrument interprets commands.
We consider the head path as a string which will be inserted in front of
every command of a message. As for the first command of a message, the
head path is a null string; for each subsequent command, the head path is
a string which is defined to form the current command until and including
the head of the last colon separator. A message with two combined
commands:
CURR:LEV 3;PROT:STAT OFF
The example indicates the effect of semicolon and explains the concept of
head path. Since the head path is defined to be "CURR" after "curr: lev 3",
the head of the second command, "curr", is deleted and the instrument
explains the second command as:
CURR:PROT:STAT OFF
If "curr" is explicitly included in the second command, it is semantically
wrong. Since combining it with the head path will become
"CURR:CURR:PROT:STAT OFF", resulting in wrong command.
Movement in the Subsystem
In order to combine commands from different subsystems, you need to be
able to reset the header path to a null string within a message. You do this
by beginning the command with a colon (:), which discards any previous
header path. For example, you could clear the output protection and check
the status of the Operation Condition register in one message by using a
root specifier as follows:
PROTection:CLEAr;:STATus:OPERation:CONDition?
The following message shows how to combine commands from different
subsystems as well as within the same subsystem:
POWer:LEVel 200;PROTection 28; :CURRent:LEVel 3;PROTection:STATe ON
Note the use of the optional header LEVel to maintain the correct path
within the voltage and current subsystems, and the use of the root specifier
to move between subsystems.
Including Common Commands
You can combine common commands with subsystem commands in the
same message. Treat the common command as a message unit by
separating it with a semicolon (the message unit separator). Common
commands do not affect the header path; you may insert them anywhere in
the message.
VOLTage:TRIGgered 17.5;:INITialize;*TRG
OUTPut OFF;*RCL 2;OUTPut ON
Case Sensitivity
Common commands and SCPI commands are not case sensitive. You can
use upper or lower, for example:
*RST = *rst

ITech IT7900 Series Specifications

General

Brand	ITech
Model	IT7900 Series
Category	Power Supply
Language	English