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how to separately display modbus input registers using a graph to display each register

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I have a Modbus RTU program which is over RS485 it communicates reads/write 

now I want to graph 5 input registers on my front panel

I am new to LabView can anyone give me some example or a simple way to do it


thank you 




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Message 1 of 11


I am trying to communicate to an inverter with Modbus RTU  over rs485 and I got to communicate to it and read the registers using the Modbus program example I got from the forum I am new to lab view 

I am new to lab view 

I want to read/write to the registers and I am unable to write can any one please suggest  me with the writing part of the Modbus registers

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Message 2 of 11

Since it is 5 different registers of a single value, you don't want to send that 1-D array directly to the waveform chart as it will interpret that as 5 samples of a single channel.  So put a Build Array on that wire to turn it into a 2-D array to send to the chart.


If you want it on 5 different graphs,, then you need to use index array to break them out.  (In which case you should also look at the online LabVIEW tutorials)
LabVIEW Introduction Course - Three Hours
LabVIEW Introduction Course - Six Hours

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Message 3 of 11

that doesn't work

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Message 4 of 11

What doesn't work?


Attach your code.  Give some detail as to how it is not working and how it is different from how you expect it to work.


If your car broke down, you wouldn't call the repair shop and just say "it doesn't work" and expect them to tell you how to fix it over the phone.

Message 5 of 11

@Etesam23 wrote:

that doesn't work

It is impossible to tell exactly what you are doing from va picture of part of the code.


You need to know which U16 element is what register. And the scaling of each register.  The device manual would be a great help if you read it.  Then just wire those scaled values to a CHART.

"Should be" isn't "Is" -Jay
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Message 6 of 11

Am  sorry for "doesn't work"

attached is my code

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Message 7 of 11

You have some bad habits.


Hidden FP Objects (Controls / Indicators) that are not wired to the connector pane are basically "Constants"  So- STOP THAT!  It makes you look like a simple text programmer!


Alright, so, now that you have apologized for the vague statement "Doesn't work.", would you care to elaborate on that statement?  <D'oh!- we still don't know what the device is. Or what registers you want to display graphically> 

"Should be" isn't "Is" -Jay
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Message 8 of 11


    I am using Modbus TCP view from as a slave device and connected that it to my lab view program (which I already posted) as master ( this is my bench test ) both are connected through null modem

I will be using this for my dc converter bench model for displaying the wave forms of voltage current and so on 

so I just wanted to display each of the input registers in the form of the graph because my c program has input registers which have voltage current so on.....................



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Message 9 of 11
Accepted by topic author Etesam23

Replace the graph with a chart  Insert "Array to Cluster" and set the cluster size to the number of elements you want to display

"Should be" isn't "Is" -Jay
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Message 10 of 11