Design And Implementation Of Flexible Hardware Platform Based On PIC Microcontroller

In embedded development, some of the functional modules that are designed based on PIC microcontroller are repeatedly used frequently, such as communication module, display module. The software needs to be debugged after the embedded hardware devices are designed. If the functional modules have been debugged before, the corresponding sources code can be transplanted to the new hardware devices. Then, before used, the code associated with the hardware needs to be re-edited. However, when the function of modules is much more complex and the amount of code is much larger, the corresponding parts of the hardware require to be found from the sources code. In addition, large amount of source code will make the process more tedious, the program more prone to error, and the debugging more difficult.In this paper, based on the C30 and C18 compilers used in PIC microcontroller integrated development environment MPLAB IDE, a flexible hardware platform is designed for some functional modules and class of algorithms source code which can be used simply in the following development. According to updating software of the embedded devices with the Bootloader that is used in PIC microcontroller currently, an improved way that the user application code in the program memory block is cleaned completely before writing the new HEX files is proposed.Firstly, according to the project requirement, based on PIC microcontroller the hardware circuit is designed, on the basis of which the Ethernet communication module, real-time clock module, external storage module, LCD display module and RS-485 module are debugged. The software is designed with the real-time operating system based on PIC microcontroller.Secondly, the use of PIC compilers is more deeply studied. Based on the source code of functional modules which have been developed before, the source files are packaged into library files with some executable files included in the compilers. These library files can be used directly in software development based on PIC microcontroller. This will make the amount of code much smaller and the development much simpler. Besides, this will not only achieve general, because integrating many files into one will make the link easier, but also be helpful to maintain the code with assembling the related modules. Because the provided functional library functions have already been processed before to be binary files that can be relocated, the efficiency will be improved greatly in software compilation.Thirdly, when updating software of embedded devices based on PIC microcontroller by the traditional Bootloader way, the user application code in the program memory block should be cleaned completely before writing the whole new HEX file, which will make the efficiency lower. So, using a new method to improve the Bootloader will both guarantee the reliability and simplify the process of software updating.Finally, in a new project, the flexible hardware platform based on PIC microcontroller and the improved Bootloader are both used to update software. This makes some functional modules simply to debug, and takes less time. This also improves the efficiency in updating software, and makes the system more steady after updating. This proves that using the flexible hardware platform in the new development can shorten the development cycle without influencing the stability of the system, and the improved Bootloader is feasible, efficient and reliable.