Dual Mcu Main Controller Of The Gas Water Heater Design

In the current use of smart thermostatic gas water heater controller, typically use one MCU and the embedded software, as the core of the controller to complete a variety of control functions; on the other hand, in controller, gas solenoid valve drive circuit of the physical connection for the hardware: the output port of MCU + driver or isolation devices + power transistors or relays. As a power transistor or relay controlled electronic switch, connect one end of drive power, and connect the other end of the solenoid valve. However, these two common modes there are some security risks, this is because: 1,the MCU itself, including the thousands or tens of thousands of electronic transistors. When the MCU's hardware or software (embedded software) failure or loss of control, it will be dangerous; 2, when the power transistor or relay short-circuit fault occurs, the drive power will be directly loaded into the solenoid valve, so that the solenoid valve open, resulting in gas leak, it will be dangerous.In this paper, to address these issues the author puts forward a new kind of gas water heater dual MCU controller based on embedded and distributed multi-machine system, the controller using a dual microcontroller controls the whole system together to complete. When the system control, dual-MCU to complete a specific signal detection were collected and the test signals and their work status information to communicate with each other, two microcontrollers use the other to pass information to monitor and control. Dual MCU through serial communication (UART) mode to connect, mutual coordination and cooperation and mutual monitoring, the common complete system control and improve the overall control system security and reliability. To avoid the security risks or dangerous caused by the failure or out of control of one MCU, and to minimize the possibility of dangerous degree by the automatic control system failure, as the same time to complete the design of more compact, reducing manufacturing costs.