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Using minimum and maximum, Using queries, Note – Xantrex Technology XDC User Manual

Page 198: Terminating characters, Common commands

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SCPI Command Reference
Using SCPI Commands

196

Operating Manual for XDC Series Power Supply

Angle brackets ( < > ) identify where specific values must be entered for a

parameter. For example, in the example at the top of the page, the parameter

appears in the command string. To set the current setpoint to 0.1A, the

syntax is CAL:CURR:LEV 0.1.

Square brackets ( [ ] ) identify optional parameters. If an optional parameter is

not sent with the command string, a default parameter is sent in its place.

Using

Minimum and

Maximum

In the following example, Minimum and Maximum are offered as alternative choices
to declaring a specific parameter value.

CAL:CURRent:LEVel {|MIN|MAX}

The string CAL:CURR:LEV MIN sets the current calibration level to the minimum

model value.

Using

Queries

A question mark lets you query the present value for most parameters. For example,
to query the current calibration state use:

CAL:SEC:STAT?

You can also use the following to query minimum and maximum allowed values for
most parameters:

:VOLT? MIN
:VOLT? MAX

Terminating

Characters

Every command string must end with a terminating character. An
IEEE-488 EOI (end-or-identify) can be used instead of a character. It is
also acceptable to use a followed by a . Terminating a
command string always resets the SCPI command path to the root level.

Common

Commands

The IEEE-488.2 standard includes a set of common commands for functions such as
reset and self-test. These common commands always start with an asterisk (*),
contain 4 or 5 characters, and may have one or more parameters. The command is
always separated from the parameter by a blank space. Multiple commands sent in
the same string are separated by a semi-colon (;). The following is an example of
how 3 common commands can be sent together in the same string:

*OPC; *PSC Off; *TRG

Note If you send 2 queries, it is best to read and respond to the first response before trying

to read the second. Otherwise, you may receive an incomplete first response followed by a

complete second response. To avoid this, you can either wait for and read the first response

before sending the second query, or send a device clear message before sending the

second query.