Using A Semicolon (;); Using A Comma (,); Using Whitespace; Using "?" Commands - Agilent Technologies N1911A Programming Manual

1 Power Meter Remote Operation
down one level in the present path (for the specified root- level command)
of the command tree. You must separate command mnemonics from each
other using a colon. You can omit the leading colon if the command is the
first of a new program line.

Using a Semicolon (;)

Use a semicolon to separate two commands within the same command
string. The semicolon does not change the present path specified. For
example, the following two statements are equivalent. Note that in the first
statement the first colon is optional but the third is compulsory.
:DISP:FORM DIG;:DISP:RES 2
:DISP:FORM DIG;RES 2

Using a Comma (,)

If a command requires more than one parameter, you must separate
adjacent parameters using a comma.

Using Whitespace

You must use whitespace characters, [tab], or [space] to separate a
parameter from a command keyword. Whitespace characters are generally
ignored only in parameter lists.

Using "?" Commands

The bus controller may send commands at any time, but a SCPI
instrument may only send responses when specifically instructed to do so.
Only query commands (commands that end with a "?") instruct the
instrument to send a response message. Queries return either measured
values or internal instrument settings.
72 N1911A/1912A P-Series Power Meters Programming Guide