| 摘要 |
The present invention relates to methods and apparatus for ascertain time and date in a telecommunications system, which comprises a mobile equipment (2), a management system (20) and an add-on accessory (1), connected physically or by wireless connection to the mobile equipment (2). The add-on accessory (1) needs to know the current time and date for different reasons. This information is retrieved either from the mobile equipment (2) or from a real-time clock built into the add-on accessory (1). Since the clock may slow over time and can additionally be set to an incorrect value by the user, the clock is compared to the time and date of the management system (20) at a regular basis to ensure correct operation. Clock information is sent using the Short Message Service (SMS) of a mobile network (25). In order to accommodate varying delays experienced when sending and receiving SMS messages, the updating procedure is further refined. |
