Using The Expanded System - Keithley 2651A Reference Manual

Section 6: Instrument programming
An attempted TSP-Link reset will fail if any of the following conditions are true:
•
Two or more instruments in the system have the same node number
•
There are no other instruments connected to the unit performing the reset (only if the expected
number of nodes was not provided in the reset call)
•
One or more of the units in the system is not powered on
•
If the actual number of nodes is less than the expected number
The programming example below illustrates a TSP-Link reset operation and displays its state:
tsplink.reset()
print(tsplink.state)
If the reset is successful, online will be output to indicate that communications with all nodes have
been established.

Using the expanded system

Accessing nodes
A TSP-Link
an entry in this table. Each entry is indexed by the node number of the unit. The variable node[N]
(where N is the node number) is used to access any node in the system. For example, node 1 is
represented as entry node[1] in the node table.
Each of these entries is a table holding all of the logical instruments (and associated commands)
shared by the corresponding unit (see Logical instruments for more details). Source-measure unit
(SMU) A on node 1, therefore, could be accessed as node[1].smua.
The variable localnode is an alias for node[N], where N is the node number of the node on which
the code is running. For example, if node 1 is running the code, localnode can be used instead of
node[1].
The following programming examples illustrate how to access instruments in the TSP-Link system
(shown in TSP-Link connections):
•
Any of the following three commands can be used to reset SMU A of node 1 (which, in this
example, is the master). The other nodes in the system are not affected.
smua.reset()
localnode.smua.reset()
node[1].smua.reset()
•
The following command will reset the SMU A of node 4, which is a subordinate. The other nodes
are not affected.
node[4].smua.reset()
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Model 2651A High Power System SourceMeter® Instrument Reference Manual
®
reset() command populates the node table. Each unit in the system corresponds to
2651A-901-01 Rev. A / March 2011