while (my ($home, $topics)=each(%topics)){  # should be %ttopics

##</code><code>##

sub tHelp
{\%ttopics
my $startpoint=$target;

##</code><code>##

# some where in the part that calls tHelp:

   tHelp( $param1, \@array );  # or whatever...

# in tHelp itself:

sub tHelp
{
    my ( $param, $aref ) = @_;
    ...
}