Dear coleagues,

I have a problem in establishing ethernet communication between PLC S7-1200 and Vijeo Citect SCADA over ethernet using PSDIRECT driver.

I installed and configured driver according to manual (see attached picture). On SCADA I defined PLC variable - also can be seen in attached picture.

On SCADA application I can see all PLC variables and it works perfectly (real, bool variables)! But the problem is when I want to write variable - I can not write, PLC variable can not be changed!

PLC program is not overwriting that variable. Variable is in data block. Data block has option Optimize block access unchecked. PUT/GET communication is enabled, full access to PLC is allowed (in manual for PSDIRECT it is requested).

I am not sure what I am doing wrong... I tried the same thing from two machines: Windows 7 and XP and result is the same. I am using virtual machines.

Do I have to, somehow, allow connections to S7-1200 from other applications? When driver is connected in online diagnostics of PLC I can see new connection: Station resources->Dynamic->Other communication.

I am doing something wrong but I do not know what!

Thanks in advance,

Milos Petrovic

Hello,

can I ask you (I'm not working with this SCADA), but under S7-1200 cfg is Read TSAP defined, but Write TSAP not, you need define same TSAP to that Write TSAP as in Read? Because this looks like you can only read to that TSAP, but not write. Can you confirm this, or simply test it and give info.

Duris_I

Hello,

can I ask you (I'm not working with this SCADA), but under S7-1200 cfg is Read TSAP defined, but Write TSAP not, you need define same TSAP to that Write TSAP as in Read? Because this looks like you can only read to that TSAP, but not write. Can you confirm this, or simply test it and give info.

Dear Duris,

I also tried to configure Write TSAP the same as Read TSAP but without success. I tested it on real PLC in my office. Maybe to configure Write TSAP in some different way!?

In attachment there are instructions for S7-1200 for this driver.

Thanks for reply!

Hello,

hmmm I don't understand one thing, till this time I was sure that this Visualisations need optimized access to PLC DB blocks, now you post that you have uncheck that flag on S7-1200 DB. Can you pls confirm this, or simply make some tests?

Duris_I

Hello,

hmmm I don't understand one thing, till this time I was sure that this Visualisations need optimized access to PLC DB blocks, now you post that you have uncheck that flag on S7-1200 DB. Can you pls confirm this, or simply make some tests?

 Dear Duris,

When I check Optimized access then driver generates errors that it could not access that data block (Reading error past end of data block-error 5). When option is unchecked  there are no errors in driver.

Duris_I

I'm sorry, as I said don't work wit this, probably now unhelpfull to you...

 Dear Duris,

Driver suddenly started to work and I am not sure WHY and HOW...

Hello 

I have a question  is it MODBUS communication ? 

Hello! 

No, it is not a Modbus communication. It is a special driver for s7-1200. On plc side I do not have to configure any protocol, just to enable PUT GET