use RPi::WiringPi; use RPi::Const qw(:all); my $pi = RPi::WiringPi->new; my ($base, $num_pins, $data, $clk, $latch) = (100, 8, 5, 6, 13); $pi->shift_register( $base, $num_pins, $data, $clk, $latch ); # now we can access the new 8 pins of the # register commencing at new pin 100-107 for (100..107){ my $pin = $pi->pin($_); $pin->write(HIGH); }