rs232 message terminator WARNING

[Leo75]

Good morning to all the forum.

I remotely command a GW Instek Programmable Power Supply PSH-6006A via LabVIEW 2012 and USB to SERIAL PORT controller. 

The power supply works properly according to the remote commands I give it via the front panel, except for this warning message:

"RS232 message terminators: AS there is no signal of end message on RS232 bus, therefore, use LF as 

message terminator. When a series of commands are sent to the instrument, it must add a LF to be a

judgment for message terminator. As for query command, the return message of the instrument is also

added a LF for PC to judge message terminator."

I made a research about it but nothing found, also have no idea about what a "LF as message terminator" is and nothing found in LabVIEW help.

Does someone know what this warning is?

Thanks in advance.

  Leo

[RavensFan]

LF is the line feed character.  It is also known as a "new line" character.  Decimal 10, hex 0A.  If you have a string constant and it is set for \codes display, it will show up as \n in the string constant.

Just make sure the command you send as that character at the end.

When configuring the serial port with the VISA configure function, make sure the termination character is enabled, and set for that character.  Which it is by default if you don't wire anything into those connectors of the function.

[GerdW]

Hi Leo,

check the VISA-SerialPortInit function. It has an input for "term char" with default value 0x0A (LF). Read the help or guess what it is good for...

[Leo75]

Very quick response, thank you! In the end I use an instrument Getting Started.vi that uses various subVI's to Initialize the driver session, configure and read a measurement from the instrument , and Close the driver session. It works properly without any error or warning message. I studied al the subVI's inside but I didn't find any termination char..... but it works!

Thank you, Kudos!

[Dennis_Knutson]

The terminator is pretty clear in the GWPS320x Write VI. Assuming you are using the driver written by Instek.

[Leo75]

Oh, you are right! Yes, I'm using Instek's drivers, but I didn't know that there were sub-sub-subVI's! 

"I learned something new also today, it's a pity to die" (cit. my friend's chief).

Thank you

  Leo