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General => Technical support => Topic started by: kenobe on May 22, 2009, 05:28:58 AM

Title: PLC to PC data communication
Post by: kenobe on May 22, 2009, 05:28:58 AM
 Hi
I am using vb.net to control a T100md888 PLC to collect pressure data from my sensor. the vb.net program is to plot the data histry.
I use the  ADC function  on the PLC to convert the pressure analog signal to digital value.
how do I then transfer this data back to my PC vb.net program .
my PC OS is window xp sp2.
Can someone pls point me to the right direction?
Thanks   :D
Title: Re: PLC to PC data communication
Post by: support on May 22, 2009, 08:36:18 AM
You can compute the actual result from the ADC readings and store them inside  DM or variable A to Z, then use the "read variable" host link commands to read them into the PC and then extract the readings (mostly in hexadecimal) and convert into useful data for plotting.
Title: Re: PLC to PC data communication
Post by: kenobe on May 22, 2009, 11:17:07 PM
Hi
Thank you for your advise.
On the vb.net side, do I need to do something special to receive the data from PLC?
I heard about tri-PLC.dll , what is it? do I need that in the vb.net program?
Thanks
Title: Re: PLC to PC data communication
Post by: support on May 23, 2009, 10:19:24 AM
That DLL is a contribution from one user. I believe the documentation that comes with the library describes how the library is to be used and what functions are available.
Title: Re: PLC to PC data communication
Post by: kenobe on May 23, 2009, 08:31:11 PM
Do you mean I can just send the serial host link commands using vb.net serial port? is that sufficient?
Thanks
Title: Re: PLC to PC data communication
Post by: support on May 24, 2009, 11:43:48 PM
As mentioned, the VB.NET is a user contribution so we do not know the details so please refer to the documentation in the zip file.

 If you download the VB6 or VB Express studio then there is and "sendCommand" function that takes care of sending out the command string and read  the response string. You will receive a response string which you need to parse into useful data.

However, it is assumed that you do have knowledge of writing in Visual Basic before attempting to use any of these library or sample project as we are unable to provide any tech support for using them. If Visual Basic is new to you, please get an entry level book to learn about it.
Title: Re: PLC to PC data communication
Post by: kenobe on May 25, 2009, 12:38:43 AM
Hi
I sincerely thank you for your advise, I think I can find the way out.
Thanks