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U6 Datasheet

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LabJack U6 Low Cost USB DAQ Device Picture

High performance multifunction DAQ with USB.

This datasheet covers all U6 variants:  U6, U6-Pro, U6-OEM, and U6-Pro-OEM.

These HTML pages form the complete datasheet, manual, and user's guide for the U6.  Most information in this datasheet applies to all U6 variants.  There is an OEM section with information specific to the build of OEM versions.  Specifications are in Appendix A.  UD library documentation is in Section 4.

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Can I use ljackuw.dll with u6 or it is only for u12?


There is a pdf sheet i have read on the web names GP_IP_LJ it is very helpful tutorial but it use ljackuw.dll so is there a tutorial for u3/6 users?

I don't know what GP_IP_LJ is.  Can you provide any further information?

Are there LabView examples available for the U6?  I saw them mentioned in the quickstart guide, but cannot find any.

Yes, start here.  A quick way to find them in the future is to just put "labview" in our search box.

My application requires 5 differenitial inputs and 4 SE inputs, is this possible, with the U6 or is it just all 14 SE or  7 DIFF inputs.

Yes, you can do any combination of differential and single-ended.  In fact, you can read all 14 single-ended and read those same channels as 7 differential at the "same" time.  Make sure you read the Differential Analog Inputs application note, as bridge circuits are the only real common example where differential inputs are needed.

Is it possible to measure and generate frequency using the same Labjack U6 at the same time?


Yes. The U6 can run four timers simultaneously. Those four can be generating or measuring in a any combination. Section 2.9 provides discusses timers in detail: http://labjack.com/support/u6/users-guide/2.9

I am using U3 HV for generating and measuring frequency using LabVIEW drivers.

Frequency Generation Mode 7 and 32-bit Frequency Measurements are working fine individually.

But when i want both to work simultaneously,the VI used (LJUD_eTCConfigSB.vi) for configuration is same,so how do i configure Timer Clock Base and TimerClockDivisor separately for generation and measurement.

The U3/U6/UE9 only has 1 timer clock that applies to all timers.  To get into more details, start a forum topic about the frequencies you are trying to generate and measure.

To get into more details, I suggest you start a forum topic.  For the outputs, let us know the range of frequency and whether they are square waves or rectangular (variable duty cycle).  For the inputs, let us know the range of frequency you need to measure.

To log a post in the forum, i am not able to login as the site always says user name or password doesn't match.

For Output frequency,the range required is from 5Hz to 1200Hz with fixed duty cycle. For Input frequency measurement,the range required is 5Hz to 500Hz. Please suggest me if the above range and channels are available, and if not till what range can i get and which module to select. 

If you are having trouble logging into the forum, please send your username and email address to [email protected].

The U6 has 4 timers and 2 counters, so not enough to do the 8 channels you need.  The toughest challenge is the 4 output square waves from 5-1200 Hz.  You could use the 4 timers in Frequency Output Mode 7, with TimerClockBase=1MHz_DIV and TimerClockDivisor=256, to get output frequencies that you can vary from 7.6 to 1953 Hz, but some of the steps would be quite course as the frequency on each timer output would be 1953/TimerValue where TimerValue is 1-256.

Perhaps your best solution is to get 4 U3s.  That would get you 4 independent frequency outputs, plus counters or timers you could use to measure input frequency.

I want to emit a square wave from one digital output on a U6 under timer control and to emit its compliment simultaneously on a second digital output. Any advice on how to accomplish this via programming?



Hi,I have tested using U6 device and CB37
I am developing in Visual C++ environment. I referenced "U6_UG_Export_20140604.pdf" and "VC6_LJUD" sample code.

I want to measure some data with U6 device.
But the target which will be measured has many pins. Also, I have two U6 devices and two CB37 boards.

I found out the sample code for measurement with two U6 devices. And I tested using this code, and it works well.
However, I cannot find the document about measurement with multi U6 devices.

I need many U6 devices more than two. So I will purchase more U6 devices if the measurement is possible.
I want to ask some questions for this issue.

1. How many U6 devices can connect to a computer??. My computer has i5 cpu core.

2. Do you have some document about this issue??



Per USB specifications, up to 127 devices can be connected to each USB host.  1 computer can have multiple USB hosts.

You mention that you found an example that reads from multiple U6s and it works.  What questions then do you have about talking to multiple devices?  The end of Section 4.3.1 shows open calls to 2 devices.