Introduction to single chip microcomputer: LED lights cycle to the left and turn on

To study the LED After the light is on and flashing , Now try to move left LED The cycle of the lamp is on .

Hardware circuit design

combination 51 Knowledge of the smallest system of single chip microcomputer , utilize AD19 Draw the minimum system circuit （ Power supply part is not included ）.

This design needs to realize 8 individual LED The cycle of the lamp is on .LED（ Light-emitting diode ） Positive connection +5V Power Supply , The negative pole is connected to the single chip microcomputer P1 mouth , In this way, as long as the SCM P1 The diode can be turned on when the output level of the port is high or low , Realization LED Light on and off .

Simulation circuit design

Simulation circuit diagram and AD The schematic drawing method is consistent , However, it should be noted that the capacitance value in the simulated minimum system reset circuit is 0.1uf, Resistance value 100Ω, And AD There are differences in the schematic diagram .

Programming

The program uses Keil5 Design ,8 position LED Program moved left ：

/*-----------------------------------------------
   name ：IO Port high and low level control 
   Content ： Cycle left to light up one LED The lamp , Shift left symbol  <<

------------------------------------------------*/
#include<reg52.h> // Include header file , In general, there is no need to change , The header file contains the definition of special function registers 
#include<intrins.h>    // Because you're going to use the left-right shift function , So add this header file 

#define led P1     // take  P1 The mouth is defined as led  You can use it later led Instead of P1 mouth 


void Delay(unsigned int t); // Function declaration 

/*------------------------------------------------
                     The main function 
------------------------------------------------*/
void main (void)
{                
  unsigned char i;  // Define an unsigned character local variable  i  Value range  0~255
  led=~0x01;
  Delay(50000); // About time delay 450ms  
  while(1)
  {  
    for(i=0;i<8;i++)
    {
      P1=~(0x01<<i);   // Move left i position , Then assign the result to P1 mouth 
      Delay(50000); // About time delay 450ms
    }
  }
}
/*------------------------------------------------
  The time delay function , Contains input parameters  unsigned int t, No return value 
 unsigned int  Is to define unsigned integer variables , The range of values is 
 0~65535
------------------------------------------------*/
void Delay(unsigned int t)
{
 while(t--);
}

Copy

Simulation Implementation

In order to intuitively feel the effect of this design , Here use protues8.7 Simulation Implementation LED Of a lamp LED The lamp moves left and turns on , See the video for details .

http://mpvideo.qpic.cn/0bf2yeaaiaaaveae7os6gnpvbqodataqabaa.f10002.mp4?