Visa Serial communication help

[control issues]

Grettings all,

My application includes talking to an FTS chiller via rs232 and pass a couple of ASCII commands.  For example to read the temperature setpoint the command is sp?.  To write the setpoint the command is sp=12.

I am able to communicate to the chiller but it happens randomly within 10-20 seconds.  Using another rs232 program works perfectly and I can poll and write immediatly. 

I am new to labview and have hit a wall.  I could not get the example read and write vi to work and got an error.

I am using version 8.5

Thank you in advance for your suggestions and or comments.

[Dennis_Knutson]

The basic serial write and read should work just like your program. Just don't delete the \r\n in the string to write. These are the '\' Codes for your CR and LF constants. Also, If you are doing a write command, you should not be trying to read anything back. The example has a case statement so that you can do your sp command and not try to read.