B&K Precision MDL Series - Programming Manual - Manual (Page 19)

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Figure 4 - Partial Command Tree
Multiple Commands in a Message
Multiple SCPI commands can be combined and sent as a single message with one message terminator.
There are two important considerations when sending several commands within a single message:
• Use a semicolon to separate commands within a message.
• There is an implied header path that affects how commands are interpreted by the
electronic load.
The header path can be thought of as a string that gets inserted before each command within a
message. For the first command in a message, the header path is a null string. For each subsequent
command the header path is defined as the characters that make up the headers of the previous
command in the message up to and including the last colon separator. An example of a message with
two commands is:
CURR:LEV 3;PROT:STAT OFF
which shows the use of the semicolon separating the two commands, and also illustrates the header
path concept. Note that with the second command, the leading header "CURR" was omitted because
after the "CURR:LEV 3" command, the header path became defined as "CURR" and thus the instrument
interpreted the second command as:
CURR:PROT:STAT OFF
In fact, it would have been syntactically incorrect to include the "CURR" explicitly in the second
command, since the result after combining it with the header path would be:
CURR:CURR:PROT:STAT OFF
which is incorrect.