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1257 User Manual
SCPI Command Basics 5-36
EADS North America Defense
Test and Services, Inc.
©
2001
The following examples show the replies to the “CLOSE?” queries.
Command:
CLOSE?
(@1(0:34))
Reply:
0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0
Command:
CLOSE?
(@1(0))
Reply:
0
Command:
CLOSE? (@1(3, 20, 31))
Reply:
1 1 1
Opening Channels
The OPEN command may be used to open channels. To say a
channel is open means:
a. The input of the channel is disconnected to the output
(Single-Pole Single Throw)
b. The input of the channel is disconnected from the “normally
open” output and connected to the “normally closed” output
(Single-Pole
Double-Throw).
The syntax for the “
OPEN
” command is:
[:ROUTe]
:OPEN <channel list>
The format for a “<channel list>” is described in the previous
paragraphs of this section of the manual.
The OPEN? command may be used to query the present state of
the channels in the system. This command returns a reply of a
sequence of “0" and “1", each of which are separated by a single
ASCII space character. The value of the reply is “1" if the
corresponding relay is opened, or “0" if the corresponding relay is
closed.
Note that this is the opposite state from the
CLOSE?
query.