2606B System SourceMeter® Instrument Reference Manual
Section 3: Functions and features
2606B-901-01 Rev. B / May 2018
3-49
Understanding LXI trigger event designations
LAN trigger objects generate LXI trigger events, which are LAN0 to LAN7 (zero based). In the
command table, the LXI trigger events can be accessed using
lan.trigger[1]
through
lan.trigger[8]
.
lan.trigger[1]
corresponds to LXI trigger event LAN0 and
lan.trigger[8]
corresponds to LXI
trigger event LAN7.
Generating LXI trigger packets
You can configure the 2606B to output an LXI trigger packet to other LXI instruments.
To generate LXI trigger packets:
1. Call the
lan.trigger[
N
].connect()
function.
2. Select the event that triggers the outgoing LXI trigger packet by assigning the specific event ID to
the LAN stimulus input.
Make sure to use the same LXI domain on both the 2606B instrument and the other instrument. If the
2606B has a different LXI domain than the instrument at the other end of the trigger connection, the
LXI trigger packets will be ignored by both instruments.
Command interface triggering
A command interface trigger occurs when:
•
A VXI-11
device_trigger
method is invoked (VXI-11 only)
•
A
*TRG
message is received
•
A USBTMC TRIGGER message is received (USB only)
Use
trigger.EVENT_ID
to monitor for command interface triggers. To ensure that commands and
triggers issued over the command interface are processed in the correct order, a trigger event is not
generated until:
•
The trigger command is executed
•
trigger.wait()
retrieves the trigger command from the command queue before it would
normally be executed
Command interface triggering does not generate action overruns. The triggers are processed in the
order that they are received in the 2606B command queue. The 2606B only processes incoming
commands when no commands are running. Unprocessed input triggers can cause an overflow in the
command queue. It is important to make sure a script processes triggers while it is running.
The command queue can fill up with trigger entries if too many
*TRG
messages are received while a
test script is running, even if the script is processing triggers. You can avoid this by using the
localnode.prompts4882
attribute (see
(on page 7-1) for more
information), and by using
trigger.wait()
calls that remove the
*TRG
messages from the
command queue. If the command queue fills with too many trigger entries, messages like
abort
will
not be processed.