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When I drop a DAQmx Task constant on my LabVIEW block diagram, I have the right-click menu option to Generate Code >>Configuration 

 

This scripts out a sub.vi that creates the Task by adding each channel with channel specific properties sequentially, one channel at a time, to repeated calls of DAQmx Configure Channel.vi.

 

I have a hard time saving that vi output!  I have not really learned how to name it properly without Using:  "BLEEP_BLEEP_BLEEP_Configuration_that_cannot_be BLEEPING_scaled.vi"

 

I believe that an autoindexing loop would be much nicer.

 

My grandmother thanks you for improving my manner of speach.

Current implementation is that FlexLogger ignores the default values as configured in the CAN database.

 

As a bonus, use the default value, max/min values for the control that points to a transmitted signal in the CAN database.

The current FlexLogger implementation requires you to connect DAQ output channels to input channels and an additional XNET port to log output CAN signals, which adds to the cost of the DAQ setup/limits the amount of DAQ/chassis.

Very annoying this isn't possible in FlexLogger (or VeriStand)

Why is there no way to determine Trigger Status in NI-Scope? 

 

No, "Acquisition Status" is NOT the same thing. As Acquisition Status only tells you if acquisition is complete. I suppose you could say if it's not complete then it is still waiting for trigger, but you could be wrong. Specially in the case of a slow acquisition (seconds/div).

 

Any modern DSO I have used had a VI to determine Trigger Status and would return several states.

 

Such as:

Stopped

Ready, Armed, or Waiting (pre-trigger acquisition complete, ready and waiting for trigger) 

Pre-trigger (pre-trigger acquisition in process)

Triggered (post trigger acquisition in progress)

 

当我使用网络流将数据从CRIO传输到PC时,程序正常运行几秒钟后,它提示我断开与CRIO终端的连接。此时FPGA的采样时间为1 uSec。当我将采样时间增加到大于 1 uSec 时,程序运行良好。也就是说,当程序的采样率低于1MS/S时,程序可以正常运行,当采样率等于1MS/S时,程序就会出错。是不是因为队列和网络流写得太慢了?请帮帮我,谢谢。

QQ图片20220412152952.png

I'd like to expose an opportunity to make FlexLogger easier to use around shunt calibration. With various internal shunt calibration resistors between different hardware, is there a way that the software would know the appropriate location and resistance value when performing a shunt calibration? It is tedious, and a possible point of error, having to manually enter, for example, the correct shunt resistor between using our 9236 cards and the strain based FieldDAQ units.

While using NI USB-6008/6009, I am encountering a strange error which I have failed to find the source of it. As you can see, there are 2 types of outputs. When I comment out one of the outputs, other one works fine. However, when I use them both, it gives me an error as shown below in the picture. What could be the problem?
Error : Invalid data format for digital channel
However, error direct to analog output.Error.JPG

There's no option to cancel changes made to a channel in FlexLogger. If I edit or change a series of parameters, but want to revert to the previous settings, there is no option to do so. I then need to re-enter what was there (and hope I don't forget what it was), or mash Ctrl+Z and hope I undo the correct number of steps.

 

MichaelBalzer_0-1620804223622.png

 

(Also pressing Esc on this window should perform a cancel operation and close the window).

Hi

So I have a cRIO with a 9203 mA input module. I also have sensors etc that are 4-20mA. So when it came to using the scaling feature of the shared variable as below see if you can spot the bug. 

sv1.png

So I was thinking in mA from sensor to mA input to the 9203 which is a mA module - but the RAW scale is in Amps! (Which is obvious once your colleague points it out!) Consequently I wasn't seeing any signal readings from the cRIO as 20mA << 4A. 

 

Since there is an error if you get Full and Zero around the wrong way... can there also be an error or warning if its outside the range of the module? 

 

sv2.pngsv3.png

 

Regards

Nick

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DAQmx allows to register dynamic events , but how about NI-Scope, NI-Fgen , ....   if you have an event you can route to something in hardware it should be possible to register it also as an dynamic event in LabVIEW.

 

Basically, FlexLogger limits the range of readings to the values used in the 2 point calibration.  For example, if your sensor has a range of -10 to 10 PSI, and the 2-point cal is done at +/- 10 PSI, FlexLogger will only display values within +/- 10 PSI (and will saturate otherwise).

 

I totally understand why this is done, but sensors in fact DO read above (and sometimes below) their stated ranges and have documented accuracy (i.e. 1% above 95% full scale) , so clipping the value to the scaling settings in the cal page is the wrong thing to do...the sensor can still be measuring correctly, but FlexLogger will only show the saturated value.

 

The scaling, however it is done, probably result in a Y=mX + b equation, and FlexLogger should display Y, whatever Y is, regardless of stated sensor range or 2-point cal/scaling.

 

A worse case is if the sensor has a range of +/- 10 PSI but your cal/verification system is only capable of +/- 5 PSI, you will be limited to +/- 5 PSI with the FlexLogger 2-point cal implementation.

 

Yes, there are way around this, but why should the user, usually technicians who don't necessarily understand the math or ins/outs of software, have to figure out a way around FlexLogger?

For me it is very hard to spot channel that is connected on MAX schematic below:

 

image.png

 

By changing the color of connected channel it is way easier to spot:

 

image.png

Howdy!

 

I am trying to use a data acquisition system using python. There are thermocouple  modules and voltage modules that I would like to read from. It is set up and ran in 2013 LabVIEW and I am trying to put the test system into python for easy changing of the test and user control. 

 

I am wondering if the NI-DAQmx python library is kept up-to-date and if this is possible. I have been doing a lot of nitty gritty reading through the documentation on this library because there are not many examples of data collection using python to talk to the NI sensors. After trial and error attempts I have gone back to the basics to try and see if I can even change settings in the configuration of thermocouple channels. All I am trying to do is to take measurements from the thermocouple and I am changing the units from Fahrenheit to Celsius in separate runs. I can't even get this to work, even looking at example of this from Stackoverflow and the documentation where it specifically says how to configure the thermocouple channel (https://nidaqmx-python.readthedocs.io/en/latest/ai_channel.html and Ctrl-F to find thermocouples). 

 

Here is a snippet of the code I'm writing:

try:
    with ni.Task() as task:
        
        #Add the thermocouple channels to read from NI-9214's
        task.ai_channels.add_ai_thrmcpl_chan("cDAQ1Mod1/ai0:11", name_to_assign_to_channel='',
                                             min_val=0.0, max_val=100.0, units=ni.constants.TemperatureUnits.DEG_F, 
                                             thermocouple_type=ni.constants.ThermocoupleType.T)
        task.ai_channels.add_ai_thrmcpl_chan("cDAQ1Mod2/ai0:7", name_to_assign_to_channel='',
                                             min_val=0.0, max_val=100.0, units=ni.constants.TemperatureUnits.DEG_F,
                                             thermocouple_type=ni.constants.ThermocoupleType.T)
        
        #Set the thermocouple type to T
        #task.ai_thrmcpl_type = ThermocoupleType.T
        
        #Add the voltage channels to read from NI 9209
        task.ai_channels.add_ai_voltage_chan("cDAQ1Mod3/ai0:7")
        task.ai_channels.add_ai_voltage_chan("cDAQ1Mod3/ai9:12")
        task.ai_channels.add_ai_voltage_chan("cDAQ1Mod3/ai19:27")
        task.ai_channels.add_ai_voltage_chan("cDAQ1Mod3/ai29:31")
        
        #Set the rate of the Sample Clock and samples to aquire
        task.timing.cfg_samp_clk_timing(rate=Hz, sample_mode=AcquisitionType.CONTINUOUS)
        
        #Set the ADC Timing Mode to speed up the collection
        #task.ai_channels.ai_adc_timing_mode =  ADCTimingMode.HIGH_SPEED 
        task.ai_channels.ai_adc_timing_mode = ADCTimingMode.AUTOMATIC

 

This is a little frustrating to filter through the problems because there is not much out there that has the python use for help. If you search in the documentation search, the links of the results that you can click on are broken so that is another pitfall to this method.

 

Any help is greatly appreciated but I am curious if NI will keep the python library updated and running for future use.

 

NI-DAQmx python documentation: https://nidaqmx-python.readthedocs.io/en/latest/index.html 

Stackoverflow example help: https://stackoverflow.com/questions/47479913/python-nidaqmx-to-read-k-thermocouple-value

Thermocouple example: https://www.youtube.com/watch?v=NMMRbPvkzFs

As documented in a previous post, it is currently impossible to install the nidaqmx-python library into a Docker container. Enabling this functionality would create an opportunity for software teams to build cutting edge big data pipelines for measurement instruments using container technology. This could also optimize development time by including custom DAQ code in continuous integration pipelines.

I miss the possibility to select Global Virtual Channels defined in MAX into my Flexlogger project.

It is a lot faster to setup a measurement project for systems that don't change the connected sensors so often. 

Please add support for this.

When doing PWM with DAQmx, error -200684 is thrown if a 0% duty cycle is attempted.  For situations where a true 0% is needed, this is problematic. There are a few workarounds available, but some are less than ideal.  

 

The suggestion here is to pause the output if a 0% duty cycle is attempted.

Often I need to create a simulated version of a real device in order to debug something. It would be nice if I could right-click on a real device in MAX and select "Create simulated version of this device", and it would create a simulated version of the device I'm running. This isn't so bad with standalone devices but it could make simulating modular devices easier and reduce the likelihood of a mis-click making an incorrect simulated device.

Reasoning: Those of us who work with multiple systems need to import/export configurations often, to switch from system A to B to C and so on, since names are often interfering between projects.

Idea: Provide selectable profiles in MAX - this way you could choose which of systems configurations you would like to work with without exporting/importing the systems all the time.

To change a signal name within the Digital Waveform Editor, you double-click on it and in the box that pops up, you enter a new name.  But that same name-entry box does not allow cutting and pasting of text for more mass-production of similarly-named signals. It should (allow cut and paste).