| Embedded application products are emerging in the fields such as industry control, information appliance, communication system, network system, traffic management, military defense and so on, almost everywhere. In this paper, the basic principle of ARM microprocessor is applied to study display control module which accomplish human-computer interaction in the background of an atmospheric particulate concentration monitoring project. And considering various factors such as the cost and performance of hardware resource, the security of the software system, the real-time performance and the expansion of late stage, the research designs a display control module.In the selection of microcontroller of the display control module, we take the low cost, low power factor into account, while taking the need for a strong computing power and interrupt response capability into account. Then we consider to make LPC1766 which is based on the Cortex-M3 kernel as the main control CPU. The display control module includes EEPROM memory, external FLASH memory, LCD display, JTAG debug interface, multi serial port, Ethernet port, buttons, buzzer and so on. In this paper, we have done a nuanced study of the characteristics of each device, each circuit diagram and even the PCB drawing. In order to reduce the development cost, shorten the development cycle, and take the security of the software system into account, the display control module is embedded in the μC/OS-Ⅱ real-time operating system. And we write all kinds of functions of the embedded application which is required by the module to achieve human-computer interaction. In this paper we make full use of the characteristics of μC/OS-Ⅱ and greatly facilitate the maintenance and expansion of the late function code.After the tests of the display control module it shows a strong stability, good reaction speed, convenient operation mode and the man-machine interface is friendly which can guide the customer to carry on the operations easily. This module also can communicate with the host computer through the serial port or the network port, and realize the function of data transmission, on-line control and so on. At the same time we leave a proper margin in the hardware resources in order to facilitate the expansion of the late function. |
