Serial communication

[n 516]

I am trying to use LabView program to communicate with a Temperature control instrument from NESLAB (RTE140 Bath/Circulator). The program I am using is Serial communication.vi that ships with LabView. When I write instrument command (from instrument manual) and run the program, the instrument has no response. When I use the manufacturer provided software, it works well. I did the loopback test and it works. That means there is no problem on hardware. Also, I sent the instrument command to serial port in Tera Term directly and the instrument received the command. I checked for the termination characters (\n) as well. Please help.

[rtamblin]

Serial communication can be very tricky. I would suggest you look through

http://www.ni.com/support/serial/

which contains helpful links and information on diagnosing where the problem is occurring.

Ryan Tamblin
Applications Engineer
National Instruments

[RobertoBozzolo]

I see in the serial communication.vi that the serial port is opend with default parameters (usually 9600 baud rate, 8 data bits, 1 stop bit, and no parity, but maybe in MAX or control panel are selected different parameters): are these correct for your instrument?
Second tip: which timeout have you put in the vi?
Roberto