Reserch And Development Of Handheld Devices Functional Board

With the rapid development of computer technology and informationtechnology, handheld devices has been more widely used in all aspects ofpeople’s lives，Including areas such as medical, scientific, consumer electronicsand information collection. Although the embedded technology in Domestic wasa late start, but there are a lot of companies engaged in the development ofhandheld devices products. However, these handheld devices are mostlydesigned for their specific areas, the application areas covered by these productis relatively small. Therefore, to design a handheld device functional board notfor specific professional applications in the wide caliber is of great significance.This article is based on actual demand, it elaborated the general-purposehandheld devices’ basic structure and basic knowledge involved the designprocess, which is based on PXA322processor, and analyzed the key links indetail.Combined with the comprehensiveness and flexibility, a general-purposehandheld devices functional board design scheme based on PXA322seriesprocessors is proposed. The hardware of the handheld device includes4units:the basic system module, interface module for communication systems,human-computer interaction interface module and power management module.The basic system includes PXA322, SDRAM and FLASH. In order to ensurecomplete communication function for handheld devices, we designed1channelRS232(serial port) output,1channel UART Bluetooth outputs,3USB output and10M/100M Ethernet interface. In order to improve the efficiency of thebattery-powered, extended battery time, we also joined the power managementmodule, to classify and manage the modules with different power requirements.Handheld software platform includes three parts: the Boot Loader, the embeddedoperating system and graphical user interface system. In order to facilitate thedesign, the Linux operating system can be selected, its advantages are opensource code, low hardware requirements and good real-time. The experiments show that the handheld devices functional board designprogram is feasible. Compared with ordinary domestic handheld device, thehandheld device function board is not only good performance, but also overcomethe defects of traditional handheld devices for specific areas and the poorPerformance in universal, with flexible software and hardware clipping and goodversatility.