I. Embedded Development
Embedded systems can be broadly categorized into the following four areas:
1. Embedded Hardware Development: Familiar with circuit knowledge and various commonly used components; capable of developing analog and digital circuit designs. Proficient in embedded hardware knowledge, familiar with hardware development and design patterns, and experienced in developing embedded hardware platforms using ARM 32-bit processors. Proficient in commonly used hardware design tools: Protel/PADS (PowerPCB)/Cadence/OrCad. Experience in 4-8 layer high-speed PCB design is generally required.
2. Embedded Driver Development: Proficient in Linux operating system, system architecture, computer organization principles, and data structures. Familiar with embedded ARM development, and at least proficient in Linux character driver development. Capable of porting and developing microcontrollers and ARM embedded processors, understanding hardware schematics, able to independently complete related hardware driver debugging, possessing solid hardware knowledge, and able to write software drivers based on chip manuals.
3. Embedded System Development: Proficient in Linux system configuration, processor architecture, programming environment, instruction set, addressing modes, debugging, assembly and mixed programming; proficient in Linux file system creation, familiar with various file system formats (YAFFS2, JAFFS2, RAMDISK, etc.); familiar with embedded Linux boot process and Linux configuration file modification; master the entire process of kernel trimming, kernel porting, cross-compilation, kernel debugging, bootloader writing, root file system creation and integrated deployment of Linux systems; familiar with setting up Linux software development environments (cross-compilation of libraries and environment configuration, etc.).
4. Embedded Software Development: Proficient in Linux operating system concepts and installation methods, basic Linux commands, management configuration and editors, including the VI editor, GCC compiler, GDB debugger and Make project management tool; proficient in advanced C programming, including functions and program structure, pointers, arrays, common algorithms, library function usage, and basic data structures, including linked lists and queues; mastering the basic concepts of object-oriented programming and the basics of C++; proficient in embedded Linux programming and embedded Linux development environment, including system programming, file I/O, multiprocessing and multithreading, network programming, GUI programming, and databases; familiar with common graphics libraries such as QT, GTK, miniGUI, fltk, and nano-x.
The specific tasks you'll be responsible for in a company depends on its size. Larger companies usually only assign you a module, so you'll need to be proficient in that area. Smaller companies, on the other hand, will likely require you to do a little bit of everything. You'll also need some knowledge of hardware.
II. Basic Steps of Embedded Development
Currently, embedded development has become increasingly standardized. While adhering to general engineering development processes, embedded development has its own unique characteristics. These mainly include system requirements analysis (requiring strict technical specifications), system architecture design, hardware, software, and mechanical system design, system integration, system testing, and ultimately, the final product.
(1) System Requirements Analysis. Define the design tasks and objectives, and extract the design specifications as guidelines for formal design and acceptance. System requirements are generally divided into functional and non-functional requirements. Functional requirements are the basic functions of the system, such as input/output signals and operating methods; non-functional requirements include factors such as system performance, cost, power consumption, size, and weight.
(2) System Architecture Design. This describes how the system will achieve the stated functional and non-functional requirements, including the functional division of hardware, software, and execution devices, as well as the selection of system software and hardware. A good system architecture is crucial to the success of the design.
(3) Hardware/Software Co-design. Based on the system architecture, detailed design of the system's software and hardware is carried out. To shorten the product development cycle, the design is often carried out in parallel. Most of the work in embedded system design focuses on software design. Object-oriented technology, software component technology, and modular design are methods frequently used in modern software engineering.
(4) System integration. Integrate the system's software, hardware, and execution devices together, debug them, and identify and improve errors in the unit design process.
(5) System testing. Test the designed system to see if it meets the functional requirements given in the specifications.
The most distinctive feature of embedded system development is the integrated development of software and hardware. This is because embedded products are a combination of software and hardware; the software is developed specifically for the hardware, is fixed, and cannot be modified.
