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Error 56 - Labview TCP interaction with Cognex help

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VI attached. Using Labview 2022 Q3. 


Trying to open a TCP connection with a Cognex InSight 7802 camera. 

The VI has an error 56 (source TCP Read)  which happens after I try and send the admin login. 


Flow order - TCP open connection --> TCP Read, CRLF, 100 bytes (this outputs Welcome to InSight 7802 Session 0) --> TCP Read, 6 bytes (This outputs User:) --> TCP Write, attempting to input admin\r\n --> TCP read, 10 bytes (Error 56). If it was performed properly, the below should be output. 



I've tried varying byte amount, varying the order etc but am stumped! 

Feels like it isn't sending the 'admin' command or something.


Any help would be greatly appreciated. 


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Message 1 of 4

Is that screen shot from a Telnet or SSH session? Telnet or SSH is NOT raw TCP/IP but has some more or less complex signaling (SSH also has transport encryption!)

Rolf Kalbermatter
My Blog
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Message 2 of 4
Accepted by topic author JOECAMM


Your error is in string constant! You cannot write \r\ln in a normal string constant. You have to activate code display!




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Message 3 of 4

Thanks a lot - worked immediately! 

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