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LABVIEW DSC module connect to modbus

May i ask a question about DSC Module connected to modbus

For  the DSC Module that i can create Modbus IO sever and then create varible to connected to modbus through Earthnet.

But how can i define the varible address according to modbus address.

For example i want to use 03H coil to read address 4 data. How can i define 03H coil in the labview varible address list.

 

Thanks

Daniel

 

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You just need to select the variable name and type according to this table:

http://zone.ni.com/reference/en-XX/help/371618J-01/lvmve/dsc_modbus_using/

 

I don't know what "03H" is, but if you want to read from coil#4 you'd create a boolean variable bound to 000004, if you wanted to read holding registers #5 and #6 into a single precision floating point, you'd create a sgl variable bound to F400004. My guess would be you want to subindex a register, in which case you'd ***** 400004.03. Just put this in the bind-to field of the shared variable and it will automatically grab the data for you.

 

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Hi Smithed

  Glad to receive your reply. I once read this help document before but still have some confusing about it.  What i want to read the modbus address is" The function coil is 03 and the address is 06H" . This function that i can achieve it by modbus library(read holding register.vi) read input . But i do not know how to achieve it by bound varible. 

2.jpg

  First what is the address meaning? type 06? 

 1.jpg

 

And how can i chose the boundary address. For the name of description that i choose "400001–465535 "(Holding register). But how can i define it? that i will define 400006. but follow that setup that i can not read what i want?

So may i ask how can i to define them that follow my previous description.

 

Thanks

Daniel

 

  

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Hope this post will not be sinked and any one can give me help

 

Thanks

Daniel

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With DSC 2014 release, you can choose to use Modbus LabVIEW APIs on the palette. Have you tried that?

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