According to the functional flowchart, to step in as the core, from the start step by step by step design until completion. The key to this method is a diagram drawing function. First State of the output is used to control the work process consists of several steps, conversion between the step and pointed out that workers conditions and controls of each object. This process focused on the work of all the information. At the time of programming, you can use the intermediate relay m memory step, step by step sequence, sequence control command can also be used to achieve.