Keithley DMM7510 Reference Manual

Model DMM7510
7½ Digit Graphical Sampling Multimeter Reference Manual Section 3:
Functions and features
DMM7510-901-01 Rev. B / May 2015 3-69
LAN triggering overview
You can send and receive triggers over the LAN interface. The Model DMM7510 supports LAN
extensions for instrumentation (LXI). It has eight LAN triggers that generate and respond to LXI
trigger packets.
Understanding hardware value and pseudo line state
LAN triggering and hardware synchronization are similar, except that LAN triggering uses LXI trigger
packets instead of hardware signals. A bit in the LXI trigger packet called the hardware value
simulates the state of a hardware trigger line. The Model DMM7510 stores the hardware value as the
pseudo-line state. Only the state of the last LXI trigger packet that was sent or received is stored.
The stateless event flag is a bit in the LXI trigger packet that indicates if the hardware value should be
ignored. If it is set, the Model DMM7510 ignores the hardware value of the packet and generates a
trigger event. The Model DMM7510 always sets the stateless flag for outgoing LXI trigger packets. If
the stateless event flag is not set, the hardware value indicates the state of the signal.
The instrument interprets changes in the hardware value of consecutive LXI trigger packets as edge
transitions. Edge transitions generate trigger events. If the hardware value does not change between
successive LXI trigger packets, the Model DMM7510 assumes an edge transition was missed and
generates a trigger event. The following table shows edge detection in LAN triggering.
LXI trigger edge detection
Stateless event
flag
Hardware
value
Pseudo-line
state
Falling edge Rising edge
0
0
0
Detected
Detected
0
1
0
-
Detected
0
0
1
Detected
-
0
1
1
Detected
Detected
1
-
-
Detected
Detected
You can set the LAN trigger edge detection method in incoming LXI trigger packets. The edge that is
selected also determines the hardware value in outgoing LXI trigger packets. The following table lists
the LAN trigger edges.
Trigger mode Input detected Output generated
Either edge
Either
Negative
Falling edge
Falling
Negative
Rising edge
Rising
Positive
LAN trigger objects generate LXI trigger events. LAN trigger objects generate LXI trigger events,
which are LAN0 to LAN7 (zero based). To specify the LAN trigger event in a command, use LANN,
where N is 1 to 8. LAN1 corresponds to LXI trigger event LAN0 and LAN8 corresponds to LXI trigger
event LAN7. To specify the LAN trigger event in a command, see Trigger events (on page 3-99
).

Keithley DMM7510 Specifications

General

Brand	Keithley
Model	DMM7510
Category	Multimeter
Language	English