In a method for storing messages in a communications module, the messages to be stored contain first data having a first data volume and second data having a second data volume, and it is possible for the second data volume to be different per message. It is another object to improve characteristics of a semiconductor element typified by a TFT by controlling a deposition process of a microcrystalline semiconductor film or a semiconductor film including crystal grains. Hand levers are used to turn the tractor to the left and the right.