# The first week of embedded Lessons Learned
## a, embedded course content
1. Understand the embedded technology
2. master the use of embedded Linux (command)
3 master the use of embedded Linux development tools (gcc, gbd, the make, shell)
4. grasp embedded Linux application development (files, multi-tasking, network, database)
5. understand embedded product development process (hardware - software - system)
6. Awareness of embedded system migration (u-boot, kernel, file system)
7. understand the underlying embedded software development (driven development)
## Second, what is the embedded technology?
What is prior learning embedded technology must first answer three questions
the difference between 1. and non-embedded software embedded software
2. embedded microcontroller development of the difference between development and
3. embedded development advantages and disadvantages of
non-embedded development is He said bare metal development, common non-embedded chips such as 3G mobile phones. Traditional development is the direct coupling between the software and hardware development microcontroller belong to traditional development, the development of single-chip sequence is generally schematic view, download program ---- ---- coding for the same type of different chips, usually schematics are different, so code written not apply all the chips, which need to change the code to achieve the function. The shortcomings of traditional development will be obvious:
portability 1. Software poor (poor adaptation platform), the ability to transfer from another platform to platform because each time a transfer is required to rewrite the code, the ability to adapt to poor .
2. The shortcomings of traditional development there has always existed a low efficiency, high power consumption.
3. Develop competency requirements of personnel (soft and hard take-all), a developer of software and hardware are required to master.
And embedded systems software and hardware migration between the operating system, do the upper application development on top of the operating system, do the underlying operating system under development, and the operating system equivalent of a butler, enhanced by effective management of software and hardware resources the portability of software, and the top and bottom of the development application development and operating system development engineer functional division clear. Embedded Development multitasking, provides a wealth of network protocols, providing open source software and libraries. The disadvantage is that the development of embedded hardware configuration upgrade of difficulty.
## Third, an embedded technology developers do basic standards
1. The upper layer application software development:
proficient in a language
familiar to an operating system
data structure / algorithm
2. Embedded Software Development bottom:
proficient in C (all operating systems are compiled by the C and development, since C has a pointer data type, e.g. * 0x12345678 = 0xff, all C may access the hardware directly, high operating efficiency and portability, choose a complicated operation for the C language, assembly language selected for initialization )
understand the implementation of the operating system (will be used, will be modified to add functionality)
familiar with the hardware works
familiar with assembly
therefore, reserves the knowledge of embedded systems to learn: C + language microcontroller (hardware works), the cumulative amount of code about 3w.
## Summary
1. Whether the device can be used as an embedded CPU? The answer is
2. What operating system is available as an embedded operating system?
Portable operating system that is open source code, provides a portable interface
implementation of the operating system is an important basis for measuring the operating system metrics.
