Control System Of Vending Machine Based On Embeded Operating System And CAN Bus

It must be a trend that the vending machine becomes more and more popular in China due to the rapid economic development and the acceleration of the internationalization. This paper gives a brief introduction of the present situation and the further development of the vending machine and analyze its principle, customer requirement and performance index in details based on the actual project—vending machine for cold and hot beverage, and designs the hardware circuit and software of the control system according to the requirement of the vending machine.In the hardware circuit, the 32bit ARM embedded processor and the CAN bus have been adopted. This part introduces the principle to select the CPU for the embedded system, the general outline for the hardware circuit and functional module in the cold and hot beverage vending machine. To guarantee the reliability of the system, this work designs an architecture consisting of main board and driving board. The two parts communicate through the CAN bus driven by the chips JTA 1040. According to the feature of the vending machine, this job builds up seven operation states and one control states for different systemic situations of the software. The responding flow chart for each situation is listed in the paper, in which the real time operating system ofμC/OS-Ⅱhas been adopted. The operation system has been transplanted successfully into the ARM processor on the main board and control board circuits of the cold and hot beverage vending machine respectively. Meanwhile, the task schedule has been set up according to the system structure and the communication code in the control system has been specified respectively.Lastly, the cold and hot beverage vending machine has been tested in laboratory. The expecting results for adopting the embedded ARM processor system and CAN bus communication on vending machine system have been achieved.