sub SetBitMode
  {
  my $self = shift;
  my $mask = shift;
  my $mode = shift;
  
  unless( defined( $self->{_PFT_SetBitMode} ) )
    {
    return( undef ) unless( _importDll( $self, "PFT_SetBitMode" ) );
    }

  $self->{_PFT_STATUS} = $self->{_PFT_SetBitMode}->Call( $self->{_PFT_HANDLE}, 
                                $mask, $mode );
  return( 0 ) if( $self->{_PFT_STATUS} );
  return( 1 );

  } # SetBitMode()