NE555+74LS90+74LS08 frequency divider single chip microcomputer frequency meter simulation and source code

The frequency divider NE555 counter chip + 74LS90 and 74LS08 circuit is composed, and then the signal is sent to the T1 pin of the microcontroller for detection and the digital tube display

frequency meter simulation schematic diagram is as follows

The microcontroller source program is as follows:

#include

#include

typedef unsigned char u8;

typedef unsigned int u16;

typedef unsigned long int u32;

#define shumag P2

#define gongy P1

sbit RED_KHZ=P0^1;

sbit Blue_HZ=P0^0;

sbit fengmingqi=P0^7;

unsigned char code dofly_DuanMa[10]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};

// Display segment code value 0~9

unsigned char TempData[4]; //global variable to store display value

u8 second=0;

u32 sert=0;

u32 count=0;

u16 j=0;

u16 k=0;

void delay(u16 i)

{

while(i--);

}

void display()

{

  u8 i;

        for(i=0;i<3;i++)

        {

                  gongy=i;

         shumag=TempData[i];

         delay(10);

         shumag=0x00;

        }

}

void Timer_init()

{

TMOD=TMOD|0X51;

TH0=0X3c;

TL0=0Xb0;

EA=1;

ET0=1;

ET1=1;

TR0=1;

TR1=1;

}

void main()

{

Timer_init();

while(1)

{

                if(k==20)

                {

             count=count+TH1*256+TL1;

             TempData[0]= dofly_DuanMa[count/100];

                   TempData[1]= dofly_DuanMa[count/10%10];

                   TempData[2]=dofly_DuanMa[count%10];

                  TH1=0;

                        TL1=0;

                        k=0;

                         }

                          if(count>=1000)

                        fengmingqi=0;

                         if(count<1000)

                        fengmingqi=1;

         display();

}

}

void menter0() interrupt 1

{

TH0=0X3c+TH0;

TL0=0Xb0+TL0;

j++;

if(j==20)

{

k=j;

……………………