说明：  SIMATIC+S7-200编程手册（2004年版）（中文）——本手册提供关于S7-200PLC安装和编程的信息，为工程师、程序员、安装人员和具有可编程逻辑控制器常识的电工而设计。
(SIMATIC+ S7-200 Programming Manual (2004 Edition) (Chinese)- This manual provides information on S7-200PLC installation and programming information for engineers, programmers, installers and has a programmable logic controller knowledge of electrical and design.)