Syntax: +passcode +passcode +passcode/shield +passcode/shield Sets a clearance code on a vessel or on a shield generator. If a ship has a matching code, it can pass through a vessel's blockade (+block) or land through your shield's blockage even when other ships could not. Without a string, this command wipes the current code, returning the ship or shield to a default behavior of screening out everyone. To allow everyone to pass, a ship must +unblock and shields must +shields/lower.