Commands And Queries; Substitute Parameter Names; Compound Command Structure - ILX Lightwave OMM-6810B User Manual

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C H A P T E R
The GPIB command set is designed to be intuitive yet create a simple GPIB
software development environment. In most cases commands can be
abbreviated. In this chapter, the required letters for each command are shown in
capital letters. Optional letters are shown in lower case and may be used to
improve software readability.

Commands and Queries

There are two types of device communication; commands, which tell the device to
do something and do not return anything, and queries, which return a stored value
or instrument state but do not change the device state. Queries must be
terminated with a question mark (?), while commands may require one or more
parameters to follow.
Command: "BRIGHT 5" - display brightness to maximum
Query: "BRIGHT?" - returns the display brightness level

Substitute Parameter Names

For clarity in programming, the Boolean values of one and zero may be
represented by the appropriate substitute parameter names (see Table 3.4). For
instance, the following commands are identical.
"RANGE:AUTO 1", "RANGE:AUTO ON", "RANGE:AUTO TRUE"

Compound Command Structure

Many 6810B GPIB commands require a compound structure. This is done to
distinguish between different commands of the same type.
The compound command structure is similar to a directory path structure, as
found in DOS. For example, commands which deal with the 6810B's power
display have the path "POWER:", as in the following command to set the display
units in dBm.
"POWER:MODE LOG"
Table 4.1 lists all 6810B device-dependent commands, with the full path shown for
each command and a brief description. Detailed syntax diagrams and descriptions
are provided.
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 OMM-6810B
C O M M A N D R E F E R E N C E
Terminology