SIM900A 模块测试源码，Linux和windows系统都有，拨打电话、发短信，彩信、TCPIP测试程序源码-SIM900A module test source code, Linux and windows systems have, make phone calls, send SMS, MMS, TCPIP test program source code

一个用VB编的串口助手，同时还对SIM900a支持调试(A serial port assistant compiled with VB, while also debugging SIM900a support)