controller 271 can transmit another data within every preset time limit once receiving the preset data the mouse data processor 126 can control the display 15 showing current state to the users and control the drive 121 to adjust the energy transmitted by main electromagnetic coil 11 for better power consumption and availability when the host computer 3 enter a sleep state or a user activates keystroke 16 to put the mouse into a sleep state the mouse data processor 126 will turn off the electronic switch 127 after obtaining the aforementioned state and then enter the energy conservation or sleep mode certainly either the host computer 3 or the user can activate the keystroke 16 to waken the mouse data processor 126 which will turn on off the electronic switch 127 for better energy conservation and availability to protect the mouse pad the automatic controller 128 will set limits on the max output electromagnetic energy of main electromagnetic coil in case the power line signal line 13 is not linked to host computer 3 but to usb hub of bus power or ps2 of host computer 3 there is a possibility of insufficient power for the mouse pad 1 so.