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deleting first element from a number red by VISA serial read write vi

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I want to bring the serial number of an RFID card into LAbVIEW and for that i used VISA basic serial read VI..The number red by that is in the following format.... getting a square infront of tis number....How to eliminate that square???

sorry i am very new to LAbVIEW and have no idea about this...So please help me out

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Message 1 of 3

The square indicates a non-printable character. Just use the String Subset or the Search/Split String function with the offset wired to a constant of 1.


To learn more about LabVIEW it is recommended that you go through the introduction material, tutorial(s), and other material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.

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Message 2 of 3
Accepted by topic author sathyasells

The square indicates the you recieved a "unprintable" ASCII Character.  This could be a "Start of message" indicator from the serial device.  They are often used in some communications.  Reading the device manual would be a good place to learn the expected format.  LabVIEW does have some built-in String functions like "Trim Whitespace,vi" that can removes characters that are whitespace (tabs, spaces etc..) and this snippet shows how to remove all unprintable charaters from a string. 


string class.png

"Should be" isn't "Is" -Jay
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Message 3 of 3