topic Re: Serial communication from NMITerm to LabView in LabVIEW

Serial communication from NMITerm to LabView

dannyjhu — Tue, 16 Jun 2009 15:09:15 GMT

I have a Resonance Instruments microwave that I'm trying to control through serial interface using LabView. I have controlled other serial devices for testing using the basic serial write and read vi example and I can control the microwave using NMITerm terminal I received from Resonance. But for some reason I can't get the microwave to communication with LabView.

The microwave uses the standard settings of 9600 baud rate, 8 data bits, No parity, 1 stop bit and no flow control. Using the NMITerm I can enter the example string of "T005P025O", where T is for time, 005 is five seconds, P is for setting the power, 025 is the requested watts and O starts the microwave. The string does not require a carriage return to start. As soon as I typed "O" the microwave begins heating. I can also type the letter "R" to get the current microwave settings, again no carriage return is required. Type R and up comes the settings.

I have attached a screen capture of the terminal page.

I can't figure out what I'm missing in LabView or the basic serial write and Read VI. I have tried sending the string with and without the preceeding "/" and with a number of different suffix combinations including "O\n", "O\r\n" with no luck.

Is there a specific setting I need to change for the string ending in "O" instead R for the standard carriage return? Or am I missing another setting?

Thanks for the help.

Re: Serial communication from NMITerm to LabView

Wayne.C — Tue, 16 Jun 2009 15:18:51 GMT

Danny,

Post your code so someone can take a peek.

Also suggest that you fire up NISpy and log the actual data that the NMITerm program is sending to the instrument.

Message Edited by Wayne.C on 06-16-2009 11:18 AM

Re: Serial communication from NMITerm to LabView

Coq_Rouge — Tue, 16 Jun 2009 15:27:56 GMT

If you are using '\' codes your control\constant must be set in that modus. Right click on the string item and select '\' codes display

Re: Serial communication from NMITerm to LabView

dannyjhu — Tue, 16 Jun 2009 16:27:03 GMT

Wayne, I'm using the basic serial write and read example from LabView examples. I have attached it for you.

Coq rouge, the example program has the "\" code aready set.

On the terminal program it doesn't require a "\". If the terminal program doesn't need the "\" does that mean I don't need it in LabView?

Thanks for the help.

Re: Serial communication from NMITerm to LabView

Dennis_Knutson — Tue, 16 Jun 2009 16:34:56 GMT

The terminal program may be doing it for you as you type.

Message Edited by Dennis Knutson on 06-16-2009 10:34 AM

Re: Serial communication from NMITerm to LabView

Coq_Rouge — Tue, 16 Jun 2009 16:42:52 GMT

Sorry I was somewhat slow. Your NMITerm is a dedicated program, not some hyperterm tool. So I guess you have to do some spying. Or perhaps much more easy. Ask the vendor if they can send you the communication protocol, for your instrument