The first step is to write a program that lights up an LED and burn it into the microcontroller to see the effect. The purpose is to familiarize oneself with how to write a program for the microcontroller. 2. How to burn a program. 3. Have a perceptual understanding of what the microcontroller controls. It is also the key first step to make oneself interested, because the textbooks all tell you the address of the microcontroller, and there is no actual thing about it, which is also considered difficult. I have encountered several people who say that the microcontroller is difficult because the teacher is not very clear about what they are talking about, and they only learn assembly, so they know what address to add and subtract, or transfer from this address to this address,

The second step is to write a program that allows 8 LED lights to turn on, or every two lights to turn on. The purpose of this program is to add a delay program to let everyone know about inaccurate delays.

The third step is to write a flow light program with external interrupts, which will change different patterns when there are external interrupts,

The fourth step is to write a precise delay running light program, which requires the addition of a timer program