How best to control a remote Linux app from a .NET app that uses NI-DAQmx?

[buddyh]

Need your advice in designing an application that

(1) reads and writes analog signals via a DAQ box such as PCI-6014

(2) reads and writes data and calibration commands to a remote embedded Linux application (through our LAN)

(3) contains complex calibration logic and possible database connection

I'm considering the following:

Writing a .NET application (either c# or vb) to handle requirement (3).

Using your NI-DAQmx toolbox to handle requirement (1).

Using a telnet or ssh component in .NET to handle requirement (2).

Q 1: Does this seem like a reasonable approach?

Q 2: Can you recommend a .NET telnet and/or SSH toolbox?

Thanks!

[jscape@gmail.com]

For telnet and ssh components you might consider the following.

SSH Factory for .NET

http://www.jscape.com/sshfactorydotnet/

Telnet Factory for .NET

http://www.jscape.com/telnetfactorydotnet/


buddyh wrote:
>Need your advice in designing an application that
>(1) reads and writes analog signals via a DAQ box such as PCI-6014
>(2) reads and writes data and calibration commands to a remote embedded Linux application (through our LAN)
>(3) contains complex calibration logic and possible database connection
> 
>I'm considering the following:
>Writing a .NET application (either c# or vb) to handle requirement (3).
>Using your NI-DAQmx toolbox to handle requirement (1).
>Using a telnet or ssh component in .NET to handle requirement (2).
> 
>Q 1: Does this seem like a reasonable approach?
>Q 2: Can you recommend a .NET telnet and/or SSH toolbox?
> 
>Thanks!

[David L.]

Hi buddyh

Is your Data Acquisition being done on the Linux box or a windows machine? Either way, your solution for question 1 is correct. We have DAQmx drivers for your PCI-6014, but different versions will need to be installed according to if you have windows or Linux. Windows will use DAQmx 8.3, while Linux will use DAQmx 8.0. The DAQmx for windows driver installs support for .NET as well.

What distribution of Linux are you using? Only Mandrake Linux 10.1 Official and Mandriva Linux 2006, SUSE LINUX Professional 9.2 and 9.3, and Red Hat Enterprise Linux WS 3 are supported by the DAQmx drivers. It sounds to me like you are doing almost all of the work on a windows machine, and then transferring this data to a Linux box. Is this correct? If not, can you please put a bit more detail around how all of your equipment is working and communicating?

[buddyh]

Data acquisition is being done on the Windows machine. However, the signals that are being monitored originate from the Linux box (more precisely, from a device that includes an embedded Linux box). In order to calibrate this device, I need to monitor sensors and control various valves and pumps. Some of these components are part of the device itself (internal components) and some are attached to the device for the duration of the calibration process (external components).

Data acquisition for the internal components is handled by the device electronics and those components can be read/written through an application running on the embedded Unix box - hence the need for an ssh session.

Data acquisition for the external components will go thru an NI DAQ card attached to a Windows PC. This PC will run a software application which I am tasked with writing. Because the calibration process involves reading and writing data to/from both internal and external components, my application needs to communicate simultaneously with both the DAQ box and the Linux box.

Being a little rusty on my programming skills, I'm looking for easy-to-use APIs for these communication links. It's looking like NI-DAQmx will provide a good interface to the DAQ card, and a product such as jscape's SSH Factory should provide the needed ssh client interface to the Linux application.

You've already provided the input I requested - many thanks. In addition, do you have any comments on DAQ cards? For example, in scanning the NI web site I found several cards that look like they'll meet our needs, and I can't figure out how they're different - for example, PCI-6221 versus PCI-6014. Any recommendations???

Thanks, Buddy

[David L.]

Buddy,

Glad I could help! Our E series cards are the 60xx series, and are older cards. I would definitely recommend an M series card (62xx series), which are more fully featured, higher performance, and are less expensive. A good source to help you find the correct DAQ card is NI.com/daq. This will allow you to pick out parameters you need and narrow down the proper cards for the application. If you have any questions, please do not hesitate to call our sales team at (888) 280-7645. They are very knowledgeable and will make sure you get the proper card.

Message Edited by David L. on 01-24-2007 05:09 PM

Message Edited by David L. on 01-24-2007 05:09 PM

Message Edited by David L. on 01-24-2007 05:10 PM