GPIB write is working but GIPB read doesn't work

[Terahertz]

Hello,

I wrote a LabView program to control a motion controller (Newport MM4006) via an ethernet box (National Instruments GPIB-ENET/100). Things work perfectly well in the system previously set up by someone else. I'm setting up a new system using the same models of controller and ethernet box. However, in the Labview program, only the "GPIB write" is working. The "GPIB Read" returns empty string. What can the problem be?
Many thanks.

[Dennis_Knutson]

Are you using the driver available here? I haven't used it or looked at the code but I would recomend starting with this if you're not doing so already. Are you sending a proper query? GPIB instruments don't send anything until there is a request for data. In a large number of instruments, you have to append a question mark "?" in order to request data. For example, if there's a command to set position and the syntax is "POS:X,Y", the request for position might be initiated by writing "POS?" and then doing a read. The actual commands supported for your motion controller are going to be different so you should look at the manual and look at hows
it's being done in the driver.

[Terahertz]

Thanks Denis. I'll have a look at the drivers you pointed out.

Cheers,