The Design Of Cortex-A9 Embedded Minimum System

The embedded system is used widely in modern controlling industry.However,as the central unit of embedded system,minimum embedded system has the disadvantages of high specificity,difficult to develop,and high cost.A universal minimum embedded system with Cortex-A9 microprocessor carrying Android operating system is designed to solve these problems.The main studies are as follows:According to the function requirement of embedded control equipment in modern industry,the type of the main chips and the operating system are chosen for the universal minimum embedded system.Then,the whole scheme of the hardware platform is designed.And the transportation scheme of the software is planned.In the aspect of designing hardware platform,the central IMX6 Q chip of the Cortex-A9 is employed as the main chip,and DDR3 SDRAM chips are used for expanding internal storage.The flash storage that conforms to the eMMC4.4 standard provides the storage space for the minimum embedded system.The power module,DDR3 expanding internal storage circuit,eMMC storage circuit and parts of key port circuits are designed in detail.In addition,the method for restraining the reflect of signal and crosstalk on the hardware platform is proposed by studying the signal integrity of the minimum embedded system.Lastly,eight layer PCB is tiered,the trace impedance and the layout are designed on the hardware platform.The PCB routing of the minimum embedded system platform is also completed.In the software transportation aspect,parameters of the DDR3 SDRAM are corrected.By studying the base frame of the Android operating system,the drive program of the key equipment and the functional interface are transplanted for minimum system.Finally,the functionality and the anti-interference of the minimum embedded system are test on the teach pendant.The test verified that the developed minimum embedded system can satisfy the needs of the industrial embedded equipment,and it has strong anti-interference ability which can work steadily under the condition of ±2000V electrical fast pulse transient interference and ±4000V Electro-Static discharge interference.