How to backup the parameters on EZ Path S

Hi, I need to backup the parameters on my 1998 EZ path S, but I dotn know how. I have connected a full keyboard and I know what file to copy, but I am not able to get into the dos prompt to do it. I have seen that a earlier version of the EZpath had an possibility to get into DOS prompt through the "9, utilities" by pressing "4, communication", but on the EZ path S, the "4, communication" is not an alternative. How do I get to DOS? By pressing a secret combination during boot up?