Hi, I'm trying use a USB GPIO module with LabVIEW. It uses a driver to allow serial communication with the device. I’m using the basic serial example vi that is supposed to be able to read and write to a serial device once the settings are inputted. The problem is that is won’t do either of those, while a normal terminal program with the same setting can communicate just fine. The odd thing is, there seems to be a buffer somewhere near the COM port, because none of the LabVIEWcommands will go through to the device, but if any command is sent from the terminal afterwards, it pushes an earlier LabVIEWcommand through first. Even with the Labview program closed. The read function in LabVIEW also tends to return whatever the write function sent. I would appreciate any insight or advice!

From YOUR NUMATO manual page 10 3. To send a command to the module, use an API equivalent to write/writefile and pass the buffer/string containing the command. It is important to append Carriage Return (ASCII 13) to emulate the ENTER key The code you posted is using a \n (ASCII 10) Line Feed or New Line You need to use \r (ASCII 13) Carriage Return

LabVIEW

Serial Communication Not Functioning Fully

Solved!

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That would make sense.. So can I just change the termination character in the VISA Write.vi? It says \n=0xA, but I'm not sure what value to replace 'A' with to get the \r.

Thanks!