# main task
initialize_frobnitz();
generate_zanzibar();
show_results();

sub initialize_frobnitz {
    my $frobber = allocate_frobnitz(1);
    send_to_frobber($frobber, 'INIT')
        or die "Can't initialize frobber!";
    send_to_frobber($frobber, 'configuration value 1') 
        or die "Can't configure frobber!";
}

sub send_to_frobber {
    my $serial_port = ... etc ...