How to send commands to a MFC via a RS-485 in LabView

[ckennedy21]

I have a GE50A MFC from NI and am trying to send commands to it via a RS-485 in LabView and cannot get it to work. Has anyone built a VI for this? I have a VI that has worked previously for a p series MFC that I am trying to adapt for my g series MFC. Indicators show that I am sending the right commands to it but I cannot get a response. I tried to send commands directly though the open VISA test panel, but do not get a response that way either. Has anyone tried to do this before? Any idea? Help would be greatly appreciated. 

[Dennis_Knutson]

It's from MKS and not NI.

Since you have not provided the exact string you are sending in MAX or the programming manual, it's just a guessing game. You could have the wrong command, the right command with a wrong terminator, the wrong com setting, an incorrect cable connection, etc. Sick with MAX out another terminal emulation program until you've got the bugs worked out. Then the LabVIEW program should be a snap.

[vvnt]

Hello ckennedy21,

I have the same issue as you.

I tried to send a simple command to check baudrate

@@@001CC?;51

But I get no response.

[amazed]

Did you succeed in getting it working?   Typically, its hardware issues. Using a a rs232 to 485 adapter?    From program view,  u want to use term char 59  (semicolon) and for starters, use FF as checksum as opposed to calculating( FF tells G to ignore cksum)    

[ckennedy21]

Thanks all - It actually ended up being a wiring issue. 

Casey