From 04:00 PM CDT – 08:00 PM CDT (09:00 PM UTC – 01:00 AM UTC) Tuesday, April 16, ni.com will undergo system upgrades that may result in temporary service interruption.
We appreciate your patience as we improve our online experience.
Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Mute
- Printer Friendly Page
i/o server 2009
sf5959
Member
02-09-2010 11:53 AM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
Hello, I am trying to use the I/O server in Labview 2009 to do Modbus communication and I do not understand how it works. Does anyone have information on this and/or examples that I could use?
Thank you very much!
-Jeremy
- Tags:
- ModBus
jareds
NI Employee (retired)
02-10-2010 09:41 PM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
Jeremy,
I/O Servers allow you to communicate with various external sources of data, such as OPC servers or Modbus devices, through shared variables. Basically, once you create your I/O Server for a Modbus device, you'll create bound shared variables for the Modbus data items. Here are a couple of items on how to configure and use Modbus I/O Servers:
I hope that helps you get started with them.
Jared S.
Applications Engineering
National Instruments
Applications Engineering
National Instruments
02-11-2010 07:28 AM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
Hello Jared, Thank you for responding to my post. I have already read these links and they were not very helpful. For example, there is no explanation of whether or not I will have to pragmatically open or close the port I am using. I was able to create the communication server itself, but when I go to create specific variables for receiving data from specific addresses, I do not understand how to select the addresses I want. When I try to add a "range" of addresses to read, a list of separate variables is created. When I try to use them, nothing happens...
For the "Using Modbus I/O Servers (DSC Module or RT Module" page, there seems to be a link to view an example, but I am not able to open that link for some reason. If there is an example, is it possible for you to send it to me?
Thank you!
-Jeremy
jareds
NI Employee (retired)
02-12-2010 12:15 PM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
Jeremy,
When using I/O Servers to communicate using Modbus, you don't need to handle the closing or opening of ports. The server engine itself will handle that part of the communication. A list of separate variables is created when you add a range, because each address represents a data entry which we will represent as a variable. What type of device are you trying to connect to? When you try to use the variables, are you just trying to read from the variables?
The Using Modbus I/O Servers page is a copy of the help file from LabVIEW. The link should work when you find the page through the LabVIEW help.
Jared S.
Applications Engineering
National Instruments
Applications Engineering
National Instruments
