通过at发送手机短信.转字符串转换为Unicode代码，例如“中”的unicode代码为 4E2D，（好像是将中字的ASCII码分开，分别转成16进制）-At sending text messages via mobile phones. Turn the string is converted to Unicode code, such as " in progress"　unicode code 4E2D, (as if the word is the ASCII code in separate, respectively, convert 16 hex)