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1257 User Manual
EADS North America Defense
SCPI Command Basics 5-31
Test and Services, Inc.
©
2001
Storing the Drawer
Names in Non-
Volatile Memory
All module names presently defined may be prepared for storage
in non-volatile memory using the MODULE:SAVE command. The
actual process of updating non-volatile memory requires a
separate SYSTEM:NVUPD command. This allows multiple relay
states, exclude lists, include lists, and module names to be
updated in rapid succession, followed by a single, slower update of
the actual non-volatile memory.
All module names stored in non-volatile memory may be recalled
from non-volatile memory using the MODULE:RECALL command
.
The syntax for these commands is shown below:
[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.