1257 User Manual
EADS North America Defense
Advanced SCPI Operations 7-5
Test and Services, Inc.
©
2001
After power-up, and after a “*RST” command has been executed,
all INCLUDE lists are deleted.
Using Exclude
Lists
The 1257 provides the capability to define sets of relays which are
“mutually exclusive.” This feature is called an “exclude list.” When
one relay on an exclude list is closed, all others in the exclude list
are opened. This prevents two relays in an exclude list from being
closed simultaneously.
This feature can be used to ensure two or more relays are not
shorting system resources, such as power supplies, together.
A channel may reside on at most one exclude list. An attempt to
place a channel on a second exclude list results in an error. The
error is placed on the error queue and may be read using the
SYSTEM:ERROR? query.
A channel cannot be on an include list with another channel if it is
also on an exclude list with that second channel. That is, the
following definitions result in an error:
INCLUDE:DEF (@1(0:10))
EXCLUDE:DEF
(@1(0,11:15,6))
The error occurs because channels 0 and 6 are on an include list
together and they are on an exclude list together. This creates a
conflict since an attempt to close channel 0 would attempt to close
channel 6 due to the include list association, but would be
prevented from doing so by the exclude list.
The syntax for defining an exclude list is shown below:
[:ROUTe]
:EXCLude
<channel
list>
:EXCLude? [ <channel list> ]
:DELete
<channel
list>
:ALL
The following examples illustrate the use of this command to
define exclude lists:
EXCLUDE (@1(0:7),1(8:17))
CLOSE
(@1(0))
CLOSE
(@1(8))
CLOSE
(@1(15,17))
