The Research And Development Of Monochrome LCD Driver In The Embedded Linux

With the development of computer technology,communication technology and the in-depth application of the Internet,more and more embedded systems are running around us. And because of the increasing complexity of the Embedded systems, the embedded operating system has become the most important part of the embedded system. Embedded Linux, which is a real-time and preemptive multi-tasking operating systems, is applicable to embedded system. Now it has become a hot spot in the field of embedded system development. In the development of embedded Linux system, the most important work is the development of device driver. Excellent device drivers can make better use of hardware features, improve the efficiency of accessing and the overall performance of the application system.The driver introduced in this paper ,which is mainly used in GSM-R handset terminal for mashalling station is to support the monochrome LCD display. The handsets using the advanced European GSM-R, is important for the changing of marshalling station communication platform from analog trunk mode to GSM-R .In terms of hardware, according to the special requirements of the working environment, the project use the ARM processor as the main controller, and use monochrome LCD. On the software side, by a variety of embedded operating system, Linux has been selected as the terminal operating system. According to the specific structure and function of the hardware requirements, a complete embedded operating system is built for the further development of application program. Building work includes: customing and transplantation of embedded Linux kernel,transplantation of Bootloader, the establishment of root file system. In terms of driver, after analysing the model structure of the Linux device driver, I achieve the basic functions of this display driver module, such as opening,closing,,reading,writing, and so on. On the basis of the memory management mechanism of Linux, I achieve the distribution and mapping of the display memory. At last, According to the design of the display unit interface circuits, I achieve the control of the ARM GPIO port in Linux OS, and then through GPIO port achieve the control of the LCD display.