serial communication problems/programming HV-Source

[subzero]

Hi,
I have to programm a High voltage source (iseg SHQ262)with the serial RS-232-Interface.

With Hyperterminal i get normal access to the HV-source.
E.g.: # the source gives me back their ID-Number and specifications, U1 gives me the channel 1 voltage.

My problem is the communication Labview <-> HV-Source.
I took the serial communication VI, which is given by Labview, to test the communication, but i changed it, that it reads automatically the bytes @port.
I can see, that the direction between labview and the source is made.But when I try to receive data after sending # or another command it answers not correct.Sometimes The Read-Panel shows syntaxerror, but i tried the syntax with Hy
perterminal.
The only correct answer i get, is for # and only with activated Highlight-function.


Thanx for every help.

[Alan_L]

Subzero,

How are you sending and characters through LabVIEW?

Also, if you receive a correct response only with Highlight Execution mode enabled, then you probably don't have a programmatic delay between the serial write and read. Because it takes instruments some time to respond to commands, you need to ensure that you have a momentary pause. (Try a large number such as 1000 milliseconds and then work towards a smaller value to find the optimal delay for your instrument.)

Thank you!

Alan
Applications Engineer
National Instruments