User manual

2400 Series SourceMeter
®
User’s Manual Relative and Math 8-7
Remote math operations
Math commands
Table 8-3 summarizes commands to control the built-in math functions. See
Section 18, “Calculate subsystems,” for more detailed information on these and
other math commands.
User-defined math functions
In addition to the pre-defined math functions, you can also define your own func-
tions by using appropriate remote commands (user-defined math functions are
not available from the front panel). The following paragraphs summarize the basic
commands for user-defined functions and also list a basic programming example.
See Section 18, “Calculate subsystems,” for more details on user-defined math
functions.
Commands for user-defined math functions
Table 8-4 summarizes the commands for user-defined math functions. To define a
math function:
1. If desired, assign units to the calculation result using :CALC:MATH:UNIT.
Units is stored for the calculation.
2. Assign a name to the expression (using up to 10 ASCII characters) using
the :CALC:MATH:NAME “user-name” command.
3. Define the expression using the :CALC:MATH:DEFine or
:CALC:MATH:EXPRession command. The new expression is the one that
will be presently selected.
4. Enable the math function by sending :CALC:STATE ON.
5. Turn on the output by sending :OUTP ON, then send :INIT to trigger the
unit.
6. Request the data with the :CALC:DATA? query.
Table 8-3
Math commands
Command Description
:CALCulate:MATH:NAME <name>
:CALCulate:STATe <state>
:CALCulate:DATA?
Select match expression (name = “POWER,” “OFFCOMPOHM,”
“VOLTCOEF,” “VARALPHA”)
Enable/disable math (state = ON or OFF).
Query math data.