The ultimate fantasy of microcontrollers

Finally I have my own space, and I can't wait to post a paragraph. This is my first paragraph. With the vision of the future and the nostalgia for my past comrades and friends, I want to briefly talk about my experience of learning microcontrollers. As a kind of remembrance and memorial, I hope to give some help to friends who want to learn MCU. I first came into contact with MCU in the second semester of my freshman year, and it has been exactly four years now. It is always helpful to be good at summarizing and practicing like learning other knowledge; of course, I am not writing these to say how well I have learned, but just looking at the problems that many beginners may encounter from a certain height.

First of all, many students may think that it is outdated to talk about single-chip microcomputers now. In fact, it is not. The application range of high-end processors such as NXP lpcXX and Luminor LMSXX is fixed. At present, 4-bit, 8-bit, 16-bit and 32-bit processors exist in the market at the same time, and each has its own place. In the low-end consumer electronic product market, such as electronic watches, washing machines, etc., the advantages of MCU are very obvious in terms of cost performance. Although many chip manufacturers are working hard to improve the manufacturing process and thinking hard to solve the high cost of 32-bit machines compared to 8-bit machines, MCU is also constantly improving. The performance of Philips' MCS-51 has been improved by more than hundreds of times compared to the early 1980s. At present, 8-bit CPUs still account for 70% of the embedded market, and their advantages will still be undoubtedly to a certain extent in the next few years.

What basic knowledge do you need to learn MCU? In fact, there is no high threshold. A sophomore student majoring in electrical engineering or computer science is fully capable of introducing this knowledge. To put it bluntly, it is a little bit of analog electronics, a little bit of digital electronics, and you need to know some C language. Many students may say that they are not good at learning C. It doesn’t matter. You will understand in the process of using the language. As long as you can speak and think, and know how to abstract the phenomena and mechanisms of the real world into scientific logic (flowchart), and then implement the flowchart according to the grammar of a language, you are programming. Haha. Language is a difficult tool. Good use and expression awareness can give us a clearer understanding of the world.

What is the content of the study? Maybe many students will remember the running lights when they first learned the single-chip computer. Haha, yes, that is a classic introductory program, similar to the classic HelloWorld when learning C language, and more similar to the classic 8031\MCS-51 of Intel and Philips. What language is good for beginners to learn single-chip computer programming? Personally, I think it is better to learn some assembly. Since single-chip computers are sensitive to cost, the dominant software is still the lowest-level assembly language. It is the lowest-level language above binary machine code. Since it is so low-level, why should it be used? Many high-level languages ​​have reached the level of visual programming. Why not use it? The reason is very simple, that is, single-chip computers do not have CPUs like home computers, nor do they have massive storage devices like hard disks. Even if there is only one button in a small program written in a visual high-level language, it will reach a size of tens of K! It is nothing for the hard disk of a home PC, but it is unacceptable for single-chip computers. The utilization rate of hardware resources of single-chip computers must be very high, so although assembly is primitive, it is still widely used. The same is true. If you take the operating system and application software on a giant computer and run it on a home PC, the home PC will not be able to bear it. In addition, it is very beneficial for beginners to use assembly and deal with the underlying hardware.
In summary, I personally think that when learning, you should focus on: 1. Bus 2. Addressing mode, that is, the tricks between data, instructions, and addresses 3. Internal resources such as parallel ports, RAM, ROM, timers, etc. 4. Pay attention to the execution process of each type of instruction and basic stack operations. 5. Do more hands-on programming. Haha, there are more lessons that can only be learned after leaving school...
Cherish your youth and squander it recklessly, haha...