说明：  短信猫，at指令集合， AT 测试连接是否正确 ATE0 关闭回显。程序初始化AT部分首先关闭回显。 ATE1 打开回显。使用超级终端测试命令时打开。 AT+CGMI 得到厂商信息
(SMS cat, at the instruction set, the AT test connection is correct ATE0 off echo. The program the initialization AT part of the first turn off the echo. The ATE1 Open echo. HyperTerminal test command opens. AT+CGMI vendor information)