Rs-232 communication with humidity probe

[podge]

Hello,

Im a undergraduate student doing my 3rd year final project. I was wondering how to interface a humidity/temperature probe and display its readings. Im using a RS-1365 (www.radionics.ie     stock number 507-5807). It has a RS-232 interface. A Vi would be helpful.

[RER]

Hiya Podge,

Wow, that it quite a question. If you are unsure how to begin your application (blank VI syndrome), then the example find is always a good place to start. The examples can be used to inform or inspire yourself, or as a template – giving yourself a bit of a head start with your application development.

If you go to example finder (which can be found on the bootup splash screen OR by click help on the labview tool bar), and search for RS-232, you should be greeted with few example files. The example you should go for at this stage is the BASIC SERIAL READ AND WRITE. The example VI’s are generally well documented, and should be fairly easy to follow.

Please let us know how you get on with the serial communication examples.

Best wishes,

Message Edited by RER on 04-30-2008 05:38 AM

[podge]

hi rich,

I tried what u suggesting what you said. I went into measurement and automation program and it doesnt seem to reconise the com port. It only picks up the USB bus for my GPIB connections im using aswell for two power supplys.

[RER]

Hey Podge,

Sounds like you are missing some driver software. The two sets of drivers you probably require are NI-VISA and NI-Serial. You can check if you already have these installed, by booting up MAX (measurement and automation explorer) and expanding the “software” folder, held within the “my system” folder.

If you do not have them already installed, then follow these links to the latest versions of the software. Please check their compatibility with your version of labview and your operating system.

NI-VISA 4.3 - PharLap, VxWorks, Windows 2000/CE/Mobile 5/Vista x64/Vista x86/XP

http://joule.ni.com/nidu/cds/view/p/id/988/lang/en

NI-Serial 3.3 - Windows 2000/Server 2003/Server 2003 x64/Vista x64/Vista x86/XP/XP x64

http://joule.ni.com/nidu/cds/view/p/id/857/lang/en

Again, please let me know how you get on.

Cheers,

[Dennis_Knutson]

If it's a built in serial port, then you can skip NI-Serial. I'd also recomend that you check windows device manage first to see if the com port is listed there.

[podge]

Many thanks for the driver Rich, the probe is communicating through the com port. Another question thought, when reading the string throught the basic read and write example i get code on the read string , which i want to show the reading from the probe in decimal reading from it.

[Dennis_Knutson]

Look on your string palette. You have several functions that will convert from string to numeric (Scan From String, Fract/Exp String to Number). The function you use will depend a bit on the actual string returned. Experiment or provide an example string if you run into problems.