GameBoy\Cbopcode::cbopcode18 PHP Method

    private static function cbopcode18(Core $core)
    {
        $newFCarry = ($core->registerD & 0x80) == 0x80;
        $core->registerD = ($core->registerD << 1 & 0xff) + ($core->FCarry ? 1 : 0);
        $core->FCarry = $newFCarry;
        $core->FHalfCarry = $core->FSubtract = false;
        $core->FZero = $core->registerD == 0;
    }