I have an old Siemens S7-200 CPU 214 and it's work fine with PC/PPI cable and NI OPC Server.
The PLC haven't any programming.
The LabView "VI" diagram control I/O through OPC driver. The time response is quite slow (maybe 3 or 5 seconds) so I want try ethernet connection to speed up.
This old CPU don't support the ethernet module CP234-1.
I have a Lantronix UDS1100 Device Server in RS485 mode connected directly to PLC's RS485 pins, the OPC driver configured as "Ethernet encapsulation" and pointing to lantronix's IP.
I know that PC/PPI cable is only a RS232<->RS485 converter, then a Ethernet<->RS485 converter with RS232 commands "encapsulated" in TCP/IP packets should be work.
Well, this don't work...
Somebody can tell me why?
The parameters (baud rate, data bits, etc.) are OK.
Somebody do something similar with this or another PLC?
Thanks for your help.
Regards.