MyRIO Analog IO

I'm new to myRIO and LabVIEW. My questions are as follow:
1. I tried a simple program to acquire analog sine wave from a function generator and display it in PC (labVIEW). The sine wave displayed in labVIEW was pretty accurate for approximately 50Hz. When I increased the frequency (sweep the frequency of function generator slowly) the displayed signal was badly distorted. At some frequency, pure sine wave appeared again. The frequency of waveform displayed in PC was different from that has been set in function generator. How to configure the sampling and acquire analog signal accurately?
2. I tried to produce a sine wave at analog output port using signal generated by using 'Simulate Signal' VI. I tried the default frequency which is 10.1Hz but the waveform observed in oscilloscope was around 1 Hz. If I set the frequency to 10Hz, DC line appeared in oscilloscope.
Can anyone please point out the problems and discuss on how to solve it? I should be grateful if anyone could share some example code.
Many thanks.

trieu wrote:
Hello everybody!
I'm new to myRIO and Labview . can you help me? documents manual myRIO of ''Digital Image Processing with LabView''
thank you very much!
This qurstion seems unrelated to MyRIO analog IO, so why did you append to a seemingly unrelated thread?
Please start a new thread and explain what your question is. It is not clear what you want.
LabVIEW Champion . Do more with less code and in less time .

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NI-MyRIO Analog Inputs

Greetings,
I'm just getting the myRIO up and running, and I'm sort of disappointed that the +/- analog inputs are differential only. Is there any low level way to use these channels differently, or at least each as single-ended? Pseudo-differential, perhaps? I'm going to have to resort to using the line-level audio inputs to measure single ended inputs and make sure the input level is lower than whatever the max voltage is for that (1.7 volts or something).
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Tommy R.
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I grounded the 0- and 1- inputs of the two differential channels and had no problem measuring single ended voltages going into 0+ and 1+. I was just expecting to be able to configure the four inputs to be four single-ended inputs like I normally can do on all other NI DAQ analog hardware. The project I'm working on needs four measurments (all +/- voltages), so I was hoping the two +/- 10 channels were reconfigurable to four, like I'm used to. I'm just going to have to be creative and use the audio inputs as well.
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MyRIO analog output

I want to output an analog signal by building the analog output block in my FPGA main? How can I achieve this?

Hi Syntyche,
Could you give me a little more information about what you are trying to do? Your question is not too clear. In general to do analog output on a myRIO is using the analog output express VI http://zone.ni.com/reference/en-XX/help/373925B-01/myrioreference/myrioref_exp_ao/. Are you wanting to create a custom FPGA instead of using the default personality?

MyRIO analog input express Vi (n samples) missing file

Dear Users,
I am trying to read analog data with an express VI in myRIO. This works with Analog input (1 sample), but fails with Analog input (n samples) due a missing file "myRIO v1.1 FPGA Throughput.lvbitx".
I googled it and searched it on ni.com, but nobody seems to have the same isssue (I suppose because of the myRIO is quite new right now)
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I would try doing a repair of your installation. It looks like something didn't get installed properly.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
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MyRio analog input

Greetings,
I am new to NI and I have a question about the setting the timing on the analog inputs. I want to set up a clock (DIO output) and in addition, have ever clock rising edge initiate a single A/D conversion. Is this possible with the MyRio?
The background is I have a device with a string of sensors that will output a analog value every time I send in a clock, therefore I need to digitize the analog signal synchronized with the clock.
In addition, if someone has found documentation other than the manual, I would appreciate your sharing.
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Hi Frank,
Welcome to the forums! What you want to do is definitely possible with the myRIO. You have a few options available to you:
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Using the FPGA module to do the triggering would give you better results because of the tighter timing capabilites of the FPGA as compared to the Express VIs. The logic would be mostly the same on the FPGA as it is on the real-time except for the appropriate VIs swapped around:
Here, we are waiting for a rising edge on a digital line and then placing the data from the analog channel in a to provide this data to the host (real-time) application.
If you want absolute control over the synchronization of the AI to the clock, I would recommend implementing the logic in FPGA (2013 or 2014). If your application has a little leeway in terms of timing, the Express VIs (2013) or Interrupt Express VIs (2014) would work for you.
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Matthew B.
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Labview myRIO Analog data sampling rate

I have been using the myRIO to acquire audio input from a microphone.
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Hi ykhali,
Try putting the VI into a timed loop and set the loop rate to your sampling rate.
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How to interface multiple NTC Thermistors to a 8-1 multiplexer and then to myRIO .

I need to measure the temperature of 8 lithium ion battery cells in series individually for my battery management system . So I need to see how can I interface the 8 thermistors with 8 to 1 multiplexer and output to myRIO analog input.

Hey Bakry77,
To expand on what Jeff said you can use an analog multiplexer like this one:
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Join / Follow the LabVIEW Hacker Group on google+

MyRIO input analog signal measurement

Hi everyone,
I want to know that how to measurement the input analog signal from a signal generator to the input pin of myRIO. Is it like using myDAQ to measurement? or need to use other Labview function panel? For example, how to trigger the input signal on Labview?
If someone know this, please give me an answer.
Cheers,
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Hi Johnson,
The minimum software required to program the NI myRIO processor with LabVIEW is the following:
LabVIEW
LabVIEW Real-Time Module
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I am working on a fire-fighting robot that runs using myRio. I have a small mic plugged into the 'AudioIn' port of the myRIO and the robot has to detect a certain frequency(2.8 or 3.5 KHz) to start navigation. The AnalogIn express VI gives me raw voltage amplitudes of type 'Double' but the 'Tone Measurment' vi I wanted to use takes in a 'Signal' data type. I tried converting the raw data to dynamic data and feeding it in but did not work. One problem is that I cannot control the sample rate of the AnalogIn express VI (LabView 2013), I appreciate any suggestions on how to go about doing it.
Solved!
Go to Solution.
Attachments:
Capture.PNG ‏16 KB

Thank you all for your feedback.
@Bob_Schor the robot competition is tomorrow. Thanks for the suggestions but the High Throughput Add-on turned out to be what I was looking for.
@MilanR thank you so much. I installed LabView 2014 and the myRIO 2014 High Throughput Add-on and I now have access to low level VIs that will let me control sampling frequency and number of samples.
I am now using 'Tone measurments' to measure the frequency of the sound. But the frequency measured is not accurate, but it is atleast consistent. I am sampling at 7 KHz and taking 5000 samples at once. The two frequencies I want to detect are 2.8 KHz and 3.5 KHz. However, the mesaured frequecies I get from Tone Measurment VI are 0.400 Hz and 0.499 Hz, which are always consistent. Picture is attached below.
Attachments:
Capture3.PNG ‏10 KB

How to writing the data into the file at the same frequency of data acquisition using myRIO

Hi everyone,
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Basically, I want to acquire voltage input at analog input 0 at the frequency of 1kHz and then write the data into a file (tdms format).
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test result.xlsx ‏16 KB
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Have a look at the Jakarta POI project, they have a Java API for creating Word documents.
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Hello,
I'd like to have a 2-way audio communication using myRIO.
1. I'd like to speak into a microphone on my laptop and hear my voice on a speaker connected to myRIO.
2. I'd like to speak into a microphone connected to myRIO and hear my voice on my laptop.
3. Additonally, I need to perform the above using WiFI.
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Microphone Demo.zip ‏71 KB

Coren wrote:
Since I'm new and not very familiar with myRIO, I've 3 questions:
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2. How to send the waveform of the audio input by network stream to second application, which runs on Windows?
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Thank you.
ad.1.
myRIO is RealTime target: that means code will be executed by real time operating system on the target.
In project you will use two targets: My Computer : this is Windows target and myRIO that is real time target.
ad.2.
Check Menu>> Help>> Examples and at Search write 'Network Stream'
my second thought is it could be easier to use Shared Variables.
ad.3.
At this point important thing is target and its operating system that execute the code. For myRIO ths is Real Time Linux, for you it will be transparent, cos you will work using LabVIEW Project.
Did you start with NI myRIO Project Essentials Guide ?
Last and not least: check this path:
Rn LabVIEW: select Create Project: select Sample Projects: select Voice Recorder myRIO
Regards
Mikrobi (Zbigniew St. Sobków)____________________________________________________________
"You can lead a horse to water, but if you can get him to float on his back you've got something."

Generate sine waveform (myRio)

What is the best way to generate a 1khz sine signal on one of the analog outputs of the myRio device? I tried a timed loop and the Point by Point Sine Generation VI similar to the Electret Microphone demo or this post: http://forums.ni.com/t5/Academic-Hardware-Products-ELVIS/frequency-matching-problem-with-myrio/m-p/2... by Sammy_K. But the resolution is a problem. The frequency is not very accurate and with a dt of 100 uS and a 1Mhz Clock I only get 10 samples per period. A dt of 10 is too much load for the processor (the deivce does not respond anymore and needs to be restarted). Is there a better way of generating a 1khz sine output or do I need to do this within the FPGA somehow?
Solved!
Go to Solution.

Hey JulianR,
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LabVIEW Hacker
Join / Follow the LabVIEW Hacker Group on google+

RTD Temperature Measurements using LabView 2013 and MyRio

Hey everyone. I am VERY new to LabView programming and working with a MyRio. I need to figure out how to measure the resistance of a 2 wire RTD to find a temperature utalizing the MyRio and LabView. I am pretty lost on how to do this. Does anyone know some good resources for making the LabView program off of the tops of their heads? I've figured out how to measure from specific pins, but I am not sure how to get it to constantly output a voltage from the output pins.
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Hi JoshEpstein87,
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Hello,
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MyRIO generate/acquire by samples

Hello,
I have problem with using MyRIO. I want to acquire package of lest say 10000 samples from aquisition loop and then pass that data to next loop to analyse that data.
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I need to generate signal on analog out, acquire something from analog in and then calculate correlation and delay between these 2 signals. With Daq-mx it was easy. With MyRIO I am not so sure.
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Hey pawahan11,
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LabVIEW Hacker
Join / Follow the LabVIEW Hacker Group on google+

MyRIO Analog IO

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