VTI Instruments Corp.
APPENDIX B
42
R
EFERENCE
C
LOCK AND
T
IME
S
TAMP
The
Source
property and
TimestampSource
property in the
ReferenceOscillator
interface configure
the reference oscillator to generate an ADC sampling clock and data time stamp clock. The
PXI_CLK10 (10 MHz) or PXIe_CLK100 (100 MHz) reference signal is used by default. When the
system is synchronized to the IEEE 1588 PTP grand master via Ethernet, the IEEE 1588 clock can
be used as a reference oscillator.
S
ELF
-C
ALIBRATION
The instrument’s internal gain and offset can drift with the temperature change. It is recommended
to perform frequent self-calibration prior to the tests. The self-calibration re-calibrates complete
analog and digital signal paths using internal calibration signal source. The self-calibration,
calculates new gain and offset values of all input channels for every ranges. Because of this, the
self-calibration can be also used as a way to self-test the instrument. The self-calibration can be
performed by
Initiate
method in
Calibration. Self
interface. See Appendix for more information on
calibration.
LXI
AND
LAN
E
VENTS
When the EMX-4250/4350/4380 is used with EMX-2500 Ethernet controller (and optionally with
Platform driver), it can act as an LXI device. These instruments can be synchronized to an
IEEE 1588 PTP grand master clock. They can be armed or triggered by LAN events or they can
generate LXI LAN events to synchronize with other LXI devices through LXI Sync interface
defined by IVI standard.
EMX-2500
EMX-4250/
4350/4380
LAN Events
LAN Events
Trigger Signals
IEEE 1588
PTP Master
Other LXI
Device
Sy
n
c
Sync
LXI - Ethernet
PXI Express - Backplane
Platform
Arm/
Trigger
Event
Alarm
Arm
Trigger
Event
Trigger
Route
Digitizer/DSA
Messages
Figure 4-6: LXI and LAN Events
