Virtual cable connection

[Luciak]

Hello.

I'll try to as precise as I can because it is quite complicated.

I have V130-33-R2. It has one COM port which is configured in ladder to Modbus RTU.

Communication is ok - I read PLC via modbus.

When I want to update programme in PLC or just have online look on registers - I plug in the cable and VisiLogic do some magig and reconfigures the COM port back to PCOM mode from Modbus.

And here everything is ok also.

I have such a installation: V130 -> via cable -> GPRS modem -> via GPRS -> SCADA server -> SCADA system

And I can read registers via Modbus - everything's OK.

The problem starts at this point (I'll just mention that this works with U90 Ladder and Jazz or M-91 PLCs).

When I try to update program remotely like this: My PC -> via GPRS -> GPRS modem -> via cable -> V130

It is trying to connect and is failing - I get info as if the cable was not connected.

I tried to send to SI 115 value 0 to change it to PCOM mode (from 1 which is Modbus) and it was ok - as I saw in Info mode in communication - it had changed.

But it didn't help - still couldn't connect.

Any ideas how to do that?

[Luciak]

Solution - if any one wolud have the same concern.

What I did was putting another piece of code to set the Com Port into PCOM mode. The code was triggered by MB which I could set via ModBus.

So it works like this:

PLC is running and is transmitting data with ModBus via GPRS.

When I want to connect to PLC with VisiLogic I just send instruction/order through ModBus to reconfigure Com Port info PCOM mode.

And I can connect to PLC.

After I finish working, I just reconfigure the Com Port to ModBus and disconnect.

I have also added a timer (1 hour) which starts after I reconfigure the Com Port to PCOM.

When it is done - Com Port is reconfiguring to PCOM automaticlly.

It is just in case I forget to reconfigure Com Port to ModBus by myself.