Racal Instruments 1256E, Руководство пользователя

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1256E User Manual
SCPI Command Basics 5-34 Racal Instruments
©
2002
[:ROUTe]
:MODule
:SAVe
:RECall
These commands are NOT defined in the SCPI standard. These
commands follow the syntax rules of SCPI to implement this
functionality.
Naming a Path
A group of channels may also be assigned a name. When a group
of channels is named, it is called a “path”. A path may consist not
only of elements that must be closed (the closed channel list) but
also of elements that must be opened (the open channel list) to
complete the path. This may at first seem contradictory to close a
path with switching elements that must be opened, but it
nevertheless occurs.
A good example which illustrates the concept of an open channel
list is a typical 1P2T failsafe microwave switch. Because this type
of switch is failsafe, it only requires a single control line. By
default, with no power applied, the first throw is always connected
to the common. Energizing the control line opens the first throw
and closes the connection between the second throw and the
common. Both are obviously mutually exclusive.
Defining a path through the second throw of the example switch
can be done strictly with a close channel list. The problem occurs
when a path must go through the failsafe throw (first throw). To
make this path the switch must be in an open or off state. The
open channel list readily accomplishes this task.
Defining Path Names
The PATH:DEFINE command may be used to associate a name
with one or more relays. The format for this command is:
[:ROUTe]
:PATH
:DEFine <path name> ,
<close channel list> ,
[,<open channel list>]
The <path name> follows the same name requirements as a
<module name>, as described in the previous paragraphs.