Patent ID: 7577114

Claim:
A method for controlling a mobile communication device to enter a sleep mode and to recover timing after the sleep mode is terminated, the mobile communication device wirelessly communicating with a base station, the base station transmitting wireless signals to the mobile communication device according to a plurality of frames within a time division multiple access (TDMA) system, the mobile communication device comprising: a micro-controller unit for running a real-time operating system to load a plurality of control procedures used to control operation of the mobile communication device, the control procedures including a sleep mode managing/timing recovering program; a timing generator electrically connected to the micro-controller unit for controlling timing of the mobile communication device corresponding to the frames; and a clock generator electrically connected to the micro-controller unit for generating a first clock signal to drive the micro-controller unit; the method comprising: utilizing the micro-controller unit to execute the sleep mode managing/timing recovering program for interrupting other control procedures currently loaded by the real-time operating system; utilizing the sleep mode managing/timing recovering program to calculate a predetermined sleep period for the sleep mode where the first clock signal is stopped from driving the micro-controller unit; controlling the mobile communication device to enter the sleep mode; executing the sleep mode managing/timing recovering program for stopping the first clock signal from driving the micro-controller unit during an actual sleep period; controlling the mobile communication device to terminate the sleep mode; and executing the sleep mode managing/timing recovering program for controlling the timing generator to synchronize timing of the mobile communication device with timing of the base station according to the actual sleep period.