GW Instek GDM-8246 Programming Manual User Manual
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GDM-8246 MULTIMETER
PROGRAMMER MANUAL
⎯ 10 ⎯
command identifies it as a query.
Layer D is interrelated with device information. Different devices have
different functions. SCPI command sets belong to this layer.
Command Syntax
If you want to transfer any instructions to an instrument, and comply
with SCPI, there are three basic elements must be included.
z
Command header
z
Parameter (if required)
z
Message terminator or separator
Command Header
The command header has a hierarchical structure that can be represented
by a command tree (Figure 4).
The top level of the tree is the root level. A root node is located at the
root level. A root node and one or more lower-level nodes form a header
path to the last node called the leaf node.
Figure 4: Tree hierarchy
Leaf
:SYSTem
:AUTO
Root node
:ERRor
:STATe
:STARt
:CYCLe
Lower-level node
Leaf Node
GDM-8246 MULTIMETER
PROGRAMMER MANUAL
⎯ 11 ⎯
The command header is configured by header path and leaf node. Figure 5
shows the command header for the leaf node indicated in Figure 4.
Figure 5 Command Header
Parameter
If the commands have parameters, the values have to be included. In this
manual, when we expressed the syntax of the command, the < > symbols
are used for enclosing the parameter type. For instance, the syntax of the
command in Figure 6 includes the Boolean parameter type.
NOTE: Do not include the <, >, or | symbols when entering the actual
value for a parameter.
Figure 6 Command Header with Parameter