PLC Communication

Hie.

I'm working how to communicate with a GE Fanuc 90-70 PLC, trough Parijat. The register I use is %R Word. It works pretty fine, but when I access registers ~30->|, it messes up!

Example:

I set %R00061 to "50" and %R00061 to "60" (using Cimplicity).

I "choose to get" it (Registers 55-65) through VB/Parijat, and it shows "0". But when I choose 30-40, they appear!
What is this?

Anybody else out there working with PLCs/VB?

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NoSpamThankYouMa'am
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[Jesse]

Maybe u can try to search from net
i faced the same problem as well
but mine is PLC Melsec A series, so i am not able to help you, just to give some opinion

best regards, Jesse

Now it works fine. I just messed up the StartAdress and the DataWords properties, and got really confused...

-----------------------------------------------------
For i = GE.StartAddress to (GE.StartAddress + GE.Datawords)
List1.AddItem (GE.info(i))
Next i
-----------------------------------------------------
Was what I first wrote...


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For i = 0 to GE.Datawords
List1.AddItem (GE.info(i))
Next i
-----------------------------------------------------
Is what was right...



THE END

[Jesse]

Hi, nice to hear you've done it right.
Can i ask you some qiestion regarding PLC MelSec A series?
I don't know whether you are familiar with MelSec A series or not.
Ok, i am currently doing VB programming with this type of PLC, the objective is to receive the number - 100 from PLC.
I used MSComm control to do the communicate, and i wrote it as below:

MSComm1.Output=chr$(&H5)+"00FF0D410"
Temp=MSComm1.Input
MSComm1.Output=chr$($H6)+"00FF"

The first row of coding is to send ENQ to PLC, to ask for enquiry to read and the set Temp as input and the last row is to Acknowledge.

But everytime i run the VB, the different number will be received, even some time i OFF the PLC and the Comm Port. And each time i change the MSComm's setting, for eg: "19200,e,8,2" I will received 30, and if i change to "19200,e,7,2" I will received 29 and so on. And i don't know what had happened to cause this? And i wonder is it related with PC comm port 's conflict? Do you know how to solve it?

Best Regards, Jesse