With the widespread use of embedded system in every field, they are now becoming more and more complicated.It is important to study a method to analyse,design, verify ,code and model the system.The system uses the Finite State Diagram to analyse and design the embedded system, and at last, the software IAR VisualSTATE is used to establish the ATM system's dynamic model, whcih can produce the code automatically. This process can enhance the efficiency of the design, maintenance, and quality of software.After doing all the above, it is time to download the automatic codes and the user codes to specific hardware，such as SmartARM2200 to verify the accuracy of the modeling based on the Finite State Machine.