Character loss during write operation using VISA

[Robinet1]

Hello, I’m trying to develop a serial communication program in LabVIEW to communicate with a device and send commands, but I’m experiencing issues with data writing. It seems that the data is being transmitted; however, characters 14 and 15 of the string are missing.

If you send a character string shorter than 14 characters, the command is accepted. When using PuTTY, the full command is transmitted and executed successfully.

[crossrulz · Accepted solution]

What device are you trying to communicate with?

My initial guess here is that the device has a really small UART buffer and you are actually sending the device too much for it to handle all at once. A Putty terminal sends as fast as you type, which is horribly slow in comparison to dumping a full string into the VISA Write. If this is the case, try breaking up your serial write into 10 byte transmissions with a small delay (10ms as an initial guess) in between.

[Robinet1]

I followed your advice and now I can send commands via VISA.

Regards