[Festo, Codesys] Profibus connection between valve terminals

[mchtr]

Hi, I have two festo cpx terminals with modules fb-13 and I want to make profibus communication between them. One of them will be master, second will be slave. On both terminals I have cpx-cec controllers and fb-13 fieldbus modules. Can you tell me how to do it or give some helpful examples / materials? I found some materials on festo website but they contains instructions only for step7, nothing about codesys. I made connection between them, set switches on fieldbus modules but now all I have is bus fault on master's fb-13 and system fault on slave terminal. Sorry for my english but I hope you understand my problem.