clear command not working in target

Hi,
I am using fesh (Fat emb shell)in my target,I have included /bin/clear
command in the target but this is not working in the target…I know that i
have to give terminal type and i have to add someother stuff in the target
to make this working but i dont know what to add…?
Do anyone know what to do …?
How to use login command in the target …when add give login in my build it
is not working ,system hangs on booting …

regards
Mani