Versamax PLC modbus

Anybody can help in this case< I want to connect Versamax PLC to RTU using modbus, can I use the exixting two ports RS232 or RS 485 to do this or additional modbus card is required?Please reply asap.

You can configure the VersaMax serial ports to be a Modbus RTU master. The manual you will need is GFK_2220C and can be found here: http://support.gefanuc.com/support/index?page=docchannel&actl=MANUAL_TYPES&cat=MANUAL_TYPES

Be aware that setting up the necessary COMREQ instructions is not a task for the faint of heart.

This may help.
http://www.plcs.net/downloads/index.php?action=view&filename=GEFanuc_Commreq_Wizard.zip&directory=Other_PLC_Brands&