此程序能通过串口发送手机短信，通过AT命令实现读取、发送短信、打电话等功能，短信编码使用PDU格式，PDU编码占了程序的大量篇幅-This program to send SMS through serial port, through the AT command to read, send text messages, phone calls and other functions, the use of SMS PDU encoding format, PDU coding procedu