1257 User Manual
SCPI Command Basics 5-4
EADS North America Defense
Test and Services, Inc.
©
2001
Optional Keywords
Command keywords enclosed in square brackets are optional. For
example, the following commands are valid and equivalent:
ROUTE:CLOSE (@1(0))
CLOSE
(@1(0))
Querying Parameter
Setting
Most SCPI commands have corresponding query forms. The query
is used to read the present state of the item that is set with the
command. The query is formed by appending a question mark (?)
to the end of the command keyword.
For example, the command:
ROUTE:CLOSE (@1(0))
Has an equivalent query:
ROUTE:CLOSE? (@1(0))
The command instructs the 1257 to close channel 0 in the drawer.
The query inquires about the present open or close state of
channel 0 in the drawer.
SCPI Command
Terminator
SCPI command termination depends on whether the GPIB or RS-
232 serial interface is used.
For commands sent through the GPIB interface, a command string
sent to the 1257 must be terminated with one of the following:
1.
An ASCII linefeed character (decimal 10, hex 0A, or a
character
‘\n’).
2. The last character with the EOI signal asserted.
3. An ASCII linefeed character with the EOI signal asserted.
For commands sent through the RS-232 interface, several different
rules apply. Generally speaking, the RS-232 interface can be
accessed a number of different ways that directly impact the
termination method:
1. An ASCII linefeed character (decimal 10, hex 0A, or a
character ‘\n’).
2. An ASCII carriage return (decimal 13, hex 0D, or a character
‘\r’).
Summary of Contents for 1257
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