对SIM卡进行操作的驱动程序。实现了GSM规范中规定的基本功能。该驱动也是基于三菱M16C/60MCU的，可以方便地移植到其它平台。-SIM cards to operate the driver. To achieve the GSM specification provides the basic features. The drive is based on the Mitsubishi M16C/60MCU, can be easily ported to other platforms.