White Space; Terminators; Command Separators; Parameters - Newport LDC-3706 Series User Manual

White Space

"White space" is normally the space character. A single white space must separate a command from
its parameters or data. For example:
Table 3.2 – White Space
ACCEPTABLE
INSTR:SEL TEC
To enhance readability, one or more white spaces may be used before a comma, semicolon, or
terminator. Since the computer normally places the terminator at the end of each command string
(line), this simply means that an extra space character at the end of the command line works
acceptably.
A query has no space between the command string and the question mark. For example:
Table 3.3 – Query Formatting
ACCEPTABLE
DISPLAY?
Note: Too many consecutive white spaces can overflow the data I/O buffer.

Terminators

A program message terminator identifies the end of a command string.
termination sequences:
 <^END> (GPIB EOI)
<NL><^END>

Many computers terminate GPIB strings with <CR><NL><^END> (Carriage Return – New Line –
EOI). A carriage return (<CR>) is read as white space, and therefore has no effect on the message.
The LDC-3706 instrument terminates its GPIB responses with <NL><^END>.
If problems are encountered with GPIB communications, the termination string can sometimes be the
cause. Refer to the computer's GPIB controller manual for information on configuring its termination
string.

Command Separators

More than one command may be placed in the same command string if each command is separated
by a semicolon. The semicolon can be preceded by one or more spaces. For example:
DISPLAY ON;*IDN?;READ?
DISPLAY ON ; *IDN?; READ?

Parameters

Some commands require a parameter. The parameter must be separated by at least one white
space.
December 2019
NOT ACCEPTABLE
INSTR:SELTEC
NOT ACCEPTABLE
DISPLAY ?
46
These are the valid
LDC-3706 Series Laser Controller