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TSEP Kerberos in Productive Operation at Rohde & Schwarz

Submitted by TSEP

TSEP Kerberos is a hardware and software solution to verify the LXI functionality of test and measurement devices. TSEP Kerberos combines all the necessary components and hardware elements to perform a LXI Conformance Test. TSEP Kerberos can also be used to validate existing compliant products (regression tests) in addition to the conformance test.

TSEP Kerberos hardware creates a separate network for the device-under-test (DUT) to run, therefore it is completely sealed off from interfering influences from the outside. The hardware allows for high automation of testing due to its capability to auto-disconnect the DUT, as well as its integrated router to set all necessary network protocols and settings for IPv4 and IPv6. The Kerberos environment is also able to test Clock Synchronization (IEEE 1588) due to two Precision Time Protocol (PTP) capable network adapters which simulate PTP devices in a network. Through another separate network adapter, the main configuration of the test setup is done via a software client which is available for Windows and Linux operating systems.

The Kerberos Client communicates via TCP/ IP and can auto detect all Kerberos hardware’s in the network. The client is responsible to configure the device specific parameters and select which tests shall be run, however all configured device data as well as test-run setup will be stored on the hardware. Therefore it is possible to disconnect from the hardware once the test-run has been triggered and reconnect at a later time (or from another PC in the network) to look at the results. Use these configuration settings, exported from the client, to run automated tests with the console version of the client delivered with the TSEP Kerberos software.



IVI Web Forum Question and Answer

How to write/read custom commands?

Answered by Kirk Fertitta, Pacific Mindworks
for the
IVI Web Forum

Note:  Offering an IVI driver is a requirement for all LXI-conformant instruments, something you will find in the LXI Device Specification 2016, Section 6.1. The IVI Web Forum is hosted by the IVI Foundation.
It was created to answer the more practical questions that arise when using the IVI Drivers to program test systems. To see a list of the IVI Drivers, click here. To view this question/answer in the Forum, click here.



what can i do if i want to execute a command which is not included in the class-driver and also not in the specific driver?

Is there a write/read/query-function included in all specific drivers?

Or do i have to create a third handle with viopen to viPrintf my custom scpi-commands?



Great question. The answer is "maybe". The IVI-2014 Generation standard actually requires there be a standardized "pass-through" (aka "Direct I/O") interface in every IVI driver. Any driver with an *initial* release date on or after Jan 1st, 2015 must comply with IVI-2014. So, while most drivers you find out there were initially released before that date, the requirement of a DirectIO interface was actually just codifying practices that had been in place for years. For instance, Agilent and Keysight drivers almost certainly have a DirectIO interface. Most drivers our company has done for other major vendors include such an interface.

Where you typically find the DirectIO interface is on the instrument-specific hierarchy off a sub-interface called "System". For an IVI-COM driver, that will have a DirectIO property which returns an IFormattedIO488 pointer, which is a direct pointer to the VISA-COM DLL on which the driver is built. That is your window into the world.

The most commonly needed functions, such as "WriteString" and "ReadString' are located right there on IFormattedIO488. Note that this performs buffered I/O, about which you can best read in the VISA documentation. If you want to do unbuffered I/O and work at a lower level, then you can access the IO property on IFormattedIO488 to get the IMessage interface. If you need to do something else, then you can simply cast the IFormattedIO488 pointer to something else (IVisaSession, IRegister, IGpib, etc.).

Prior to the IVI-2014, I don't believe pure IVI-C drivers, such as those from National Instruments, commonly had a DirectIO interface, though I cannot speak as to whether or not they are updating all of them to include DirectIO.

For more comments, click here.

Thanks to all our readers.
Bob Helsel, Editor

Use the connection you already know!

New LXI Products

The LXI Consortium has certified more than 3897 instruments in over 329 product families since the specifications were first released in September 2005. Some of the recent LXI product introductions are highlighted below:

Pickering’s New 6-slot USB/LXI modular chassis – model 60-106
This 6-slot modular USB/LXI chassis occupies only a small, 1U rack-height form factor, making it suitable for portable and space-restricted rack-mount applications. The chassis accepts from one to six Pickering PXI 3U modules; the user can choose from over 1000 module types including programmable resistors, matrices, multiplexers, general purpose relays, RF switches and fault insertion units.

Keysight 34970A data acquisition / data logger switch 
The 34970A consists of a three-slot mainframe with a built-in 6 1/2 digit digital multimeter. Each channel can be configured independently to measure one of 11 different functions without the added cost or hassles of signal-conditioning accessories. Choose from eight optional plug-in modules to create a compact data logger, full-featured data acquisition system or low-cost switching unit. 

Tektronix 5 Series MSO Mixed Signal Oscilloscope
With a remarkably innovative pinch-swipe-zoom touchscreen user interface, the industry's largest high-definition display, and 4, 6, or 8 FlexChannel™ inputs that let you measure one analog or eight digital signals, the 5 Series MSO is ready for today’s toughest challenges, and tomorrow’s too. 

AMETEK Programmable Power/VTI Instruments 
The EX1401 delivers accuracies of ±0.20°C, 1000 V channel-channel isolation, built-in self-test capabilities, and independent 24-bit ADC’s per channel. Its ability to acquire data at 20K samples/second/channel allows its usage in high-speed temperature transient applications.

Textron Systems RFS340
High-Performance RF/Microwave source & vector signal generator
Textron Systems’ RF Synthesizers provide an unmatched combination of frequency coverage, power range, signal fidelity and switching speed in either a 2-slot VXI or 1U LXI® (Ethernet) format.

Kikusui Electronics PWR Series DC Power Supplies
The PWR-01 is a series of high performance, multifunctional, compact, wide-range DC power supplies. It consists of 12 models in total with 4 maximum voltage outputs (L, ML, MH, and H) and 3 maximum power outputs (400 W, 800 W, and 1200 W).

Tektronix 5 Series MSO Mixed Signal Oscilloscope
With a remarkably innovative pinch-swipe-zoom touchscreen user interface, the industry's largest high-definition display, and 4, 6, or 8 FlexChannel™ inputs that let you measure one analog or eight digital signals, the 5 Series MSO is ready for today’s toughest challenges, and tomorrow’s too.

R&S®NGE100 Power Supply Series
The R&S®NGE100 power supply series consists of robust, high-performance, affordable instruments.
-R&S®NGE102 with two, or -R&S®NGE103 with three channels

Chroma High Power DC Electronic Load Model 63200A series

  • Rated power:3kW, 4kW, 5kW, 6kW, 12kW, 18kW, 24kW, Max. 240kW (Parallel)
  • Voltage range: 150V, 600V, 1200V
  • Current range: 2,000A max. per unit
  • CC, CR, CV & CP operation modes
  • CR+CC, CR+CV, CC+CV complex modes



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