51 single chip microcomputer timing control light

Let the first small light turn on for 0.5 seconds and then turn off for 0.5 seconds.

Let's write a program to make a small light flash, taking the first small light as an example:

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1. #include   

2.    

3. sbit L1=P1^0;  

4. void main()  

5. {   

6.     int a;  

7.     while(1)  

8.     {  

9.         a=66666;  

10.         L1=0;  

11.         while(a--);  

12.         a=66666;  

13.         L1=1;  

14.         while(a--);  

15.     }  

16. }  

So how do you know how long this little light has been on?

We can debug to know when the small light is on.

First, we need to set the clock frequency of the simulator. Click Target options—>Target above, and then adjust the value in Xtal to the clock frequency of the microcontroller, which is generally 11.0592MHZ.

Then click debug to debug, double-click line 14 to make a red block appear in front of it (so that the program will pause when it reaches the red block). The page is as follows:

Then click the RST button above to rerun the program, then click Run, and then pay attention to the data in the sec item in the left column. sec represents the time it takes for the program to run to the red block.

It shows that it took 0.50006944 seconds for the program to run to the red block.

This means that the small light is on for 0.50006944 seconds.

Then we can adjust the value of a to make the small light turn on for 0.5 seconds and then turn off for 0.5 seconds.