51 MCU-Function Encapsulation

1. Clean code

Generally, the reading of single-chip microcomputer programs starts with the main function. The program writing method in the previous lecture is not concise in the main function, which affects the efficiency of reading the code. Sometimes we only need to know what a statement means, so we encapsulate the delay part into a function, and call the function name in the main function to indicate that the statement here is delayed for 1 second. This is much more readable and concise. Readers can also first understand Section 4.6 in the document "Teaching You to Learn 51 Single-chip Microcomputers Step by Step".

The principle is very simple. We can use a diagram to show what function encapsulation is.

Here, the variables i and j are simply defined in "void delay()", and the functions implemented are the same as the code in the previous lecture. However, the author found through software simulation that this will take up 4 microseconds of the CPU calling the function. For the convenience of reading, it is necessary to sacrifice these 4 microseconds. However, we do not need to add statements such as "LED2=0;" or "i=0;" at the end to solve the strange phenomenon mentioned in the previous lecture that the light jump and the stopwatch timing digital jump are not synchronized.

We recommend using function encapsulation for modular programming, because this is more in line with programming ideas and is also a programming technique we must use.

2. Suggestions

Although there is not much code in this section, we should develop the habit of reading the code from the main function instead of reading the code from the beginning. For example, the first thing that catches our eyes is the "void delay()" function. At this time, we should not enter the function body to read the content inside, but immediately find "void main()" to read and study the code inside. When we see "delay();", we have a first impression of this function with the comment, and then we can check the content of this function.

The common steps are as follows:

You must press F12 after compiling. Although the advantage of this method is not obvious when the amount of code is small, when we read other people's code, the amount of code is generally large, and this method can quickly understand the layers of meaning of the program written by others. Regarding this habit, everyone will understand it after learning the following programs.