help with changing prompt please

I am trying to write a variable to chage the prompt in Uwin from $ to router# if i tyoe export PS1="router#" at the $ prompt it owrks but if I place it in a file using the vi editor then call it it doesn't work any help wpuld be great thanks

put it into your .profile, .bashrc, .cshrc... depending on the shell you are using.

hth,
M.