METHOD FOR CONVEYING CONTROL COMMANDS FOR SIM CARD FROM EXTERNAL APPARATUS TO SIM CARD

摘要

The method according to the invention can be used for conveying low-level SIM card commands from an external apparatus (12) of a mobile station (1) to a SIM card (2) connected to the mobile station. The invention is based on locking the SIM card (2) solely for a particular control element (10) for the duration of the exchange of low-level commands. The mobile station according to the invention advantageously includes two SIM card control elements (4, 10) the first of which (4) is intended for executing commands issued by internal blocks of the mobile station and the second of which (10) is intended for conveying low-level commands from an external apparatus (12) connected to the mobile station. Said first control element (4) receives high-level commands from the various blocks (6) of the mobile station and conveys to the SIM card (2) the corresponding low-level command sequences. Said second control element (10) reserves the SIM card (2) for itselt, when necessary, whereafter the external apparatus (12) connected to the mobile station can issue low-level commands which are conveyed by said second control element (10) to the SIM card (2). Said second control element (10) frees the SIM card only when the external apparatus (12) indicates that the command sequence has ended. If said first control element (4) receives a command during the command sequence of the external apparatus, the first control element (4) remains waiting and executes the operations required by the command after the SIM card (2) has been released and is no more used by said second control element (10).