Chapter 3 95
Measurement Synchronization with LXI-B
Setting Up and Executing a List Sweep Measurement
Setting Up and Executing a List Sweep
Measurement
The following example will illustrate procedures for setting up and
executing a list sweep measurement using an MXA and an MXG
synchronized with LXI-B.
Before launching into the procedure, it is important to understand the
theory behind the method. The MXA and MXG use their LXI Output
LAN Events to communicate internal state changes to each other. In
the following synchronization, the rising edge of the
âWaitingForTriggerâ instrument event will be used to communicate to
the other device that the next step may be executed.
For clarity, the MXGâs âWaitingForTriggerâ instrument event is mapped
to the âLAN0â output event. Likewise, the MXAâs âWaitingForTriggerâ
instrument event is mapped to the âLAN1â output event. The MXA is
configured to trigger when it receives the âLAN0â event with a rising
edge. The MXG is configured to trigger when it receives the âLAN1â
event with a rising edge. Also, the âOperationCompleteâ output event is
enabled, which has the âOperationCompleteâ instrument event mapped
to it by default.
The MXGâs list sweep is started first, causing it to source the first signal
in its list. We then start the MXAâs list sweep. The âOperationCompleteâ
instrument event transitions low, causing an âOperationCompleteâ
output event to go out on the LAN with a falling edge. The MXA takes a
measurement at the first frequency in its list. When the MXA has
finished its measurement, it moves on to the next entry in its list. The
âWaitingForTriggerâ instrument event transitions high, causing a
âLAN1â output event to go out onto the LAN with a rising edge, and the
MXA waits for its next trigger.
The MXG receives the âLAN1â event and triggers. The MXGâs
âWaitingForTriggerâ instrument event transitions low, and a âLAN0â
output event goes onto the LAN with a falling edge. The MXA takes no
action, since it is configured to trigger only on rising edges. The MXG is
now sourcing the next signal in its list. Once that signal has settled, it
prepares to move on to its listâs next entry. The MXGâs
âWaitingForTriggerâ instrument event transitions high, and a âLAN0â
output event goes onto the LAN with a rising edge. The MXG waits for
its next trigger.
The MXA receives the âLAN0â event and triggers. The MXAâs
âWaitingForTriggerâ instrument event transitions low, and a âLAN1â
output event goes onto the LAN with a falling edge. The MXG takes no
action, since it is configured to trigger only on rising edges. The MXA
completes its measurement and prepares to move on to the next