Fluke 9640A Series, Instruction Manual

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SCPI and IEEE Bus Descriptions
Command Tree
4B
4B-11
Command Tree
Command Trees like the one shown in Figure 4B-11 are used to document the SCPI
command set in this manual. The keyword (mnemonic) on the root level of the command
tree is the name of the subsystem. The following example illustrates the Command Tree
of the TRIGger subsystem.
<Header>
:TRIGger
[:SEQuence]
SOURce
Parameters
SLOPe
INTernal | EXTernal
POSitive | NEGative
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Figure 4B-11. Example of the TRIGger Subsystem Command Tree
The keywords placed in square brackets are optional nodes. This means that you may
omit them from the program message.
Example:
SEND=>
TRIGger:SEQuence:SOURce INTernal
is the same as
SEND=>
TRIGger:SOURce INTernal
Moving down the Command Tree
The command tree shows the paths you should use for the command syntax. A single
command header begins from the root level downward to the ‘leaf nodes’ of the
command tree. (Leaf nodes are the last keywords in the command header, before the
parameters.)
Example:
SEND=>
TRIGger:SEQuence:SOURce INTernal
Where:
TRIGger
is the root node and
SEQuence
is the leaf node.
Each colon in the command header moves the current path down one level from the root
in the command tree. Once you reach the leaf node level in the tree, you can add several
leaf nodes without having to repeat the path from the root level.
Just follow the rules below:
You can only do this if the header path of the new leaf-node is the same as that of the
previous one. If not, the full header path must be given starting with a colon.
Command header = Header path + leaf node
Once you send the pmt (program message terminator), the first command in a new
program message must start from the root.
Always give the full header path, from the root, for the first command in a new program
message.