Introduction to using 51 single chip microcomputer to control steering gear

The steering gear （sg90, The board is common 51）

My little white , Yesterday I used 51 Several small functions of the steering gear are realized , Help a friend who is just learning like me ~(｡・`ω´･)
If there is any mistake, please give us some advice

connection

Red power supply

Brown ground

Orange data cable

Code

I hope to realize two functions

1. The foundation rotates at a certain angle
2. Realization PWM Controls the corner gradient
3. Achieve key control angle and speed ( There is a problem with the delay function , So the control effect is not good )
4. A little skill learned today , Every function realized , All should be tested in time

Program 1

// _nop_() Delay one machine cycle 
#include <reg52.h>
#include <intrins.h>
sbit PWM = P3^7;  // Set up PWM Output I/O port 
unsigned char count = 0;
unsigned char timer1 ;
/*  about 180° The steering gear  t = 0.5ms——————- The rudder turns  0 ° t = 1.0ms——————- The rudder turns  45° t = 1.5ms——————- The rudder turns  90° t = 2.0ms——————- The rudder turns  135° t = 2.5ms——————- The rudder turns 180 */

 
 
/* Delay program */
void delay1s(void)   // error  0us
{
    
    unsigned char a,b,c;
    for(c=167;c>0;c--)
        for(b=171;b>0;b--)
            for(a=16;a>0;a--);
    _nop_();  //if Keil,require use intrins.h
}
 
/* Timer T0 initialization */
void Timer0_Init()           
{
    
    TMOD &= 0x00;
    TMOD |= 0x01; // Timer T0 Set to mode 1
 
    TH0 = 0xff;   // Timing constant  0.1ms  Crystal vibration is 11.0592MHz
    TL0 = 0xa4;
 
    ET0 = 1;      
    TR0 = 1; 
	EA=1; 
	}
	
/*T0 Interrupt initialization */
void Time0_Init() interrupt 1 
{
    
	TR0 = 0; 
	TH0 = 0xff; // 0.1ms
	TL0 = 0xa4;
	
	if(count <= timer1) //5==0° 15==90°
	{
     
		PWM = 1; 
	}
	else 
	{
     
		PWM = 0; 
	}
	count++;
	if (count >= 200) //T = 20ms Zero clearing 
	{
     
		count = 0; 
	}
	TR0 = 1; // Turn on T0
}
void main()
{
    
	Timer0_Init();
	while(1)
	{
    
		
		timer1 =5;// The steering gear is restored to 0° The location of 
		count=0;// Let the timer count again 
		delay1s();
		timer1 =15;// The steering gear rotates 90°
		count=0;
		delay1s();
	}
}

Program 2

Program 2 And procedure 1 Inside count and timer1 The functions of the two values are exactly the opposite , This needs attention ...

#include <reg52.h>
#include <intrins.h>
sbit PWM = P3^7;  // Set up PWM Output I/O port 
typedef unsigned int u16;
typedef unsigned char u8;
u8 count = 0;
u8 value,timer1;// Used to adjust the duty cycle 
bit DIR;
/*  about 180° The steering gear  t = 0.5ms——————- The rudder turns  0 ° t = 1.0ms——————- The rudder turns  45° t = 1.5ms——————- The rudder turns  90° t = 2.0ms——————- The rudder turns  135° t = 2.5ms——————- The rudder turns 180 */

 
 
/* Delay program */
void delay1s(void)   // error  0us
{
    
    unsigned char a,b,c;
    for(c=167;c>0;c--)
        for(b=171;b>0;b--)
            for(a=16;a>0;a--);
    _nop_();  //if Keil,require use intrins.h
}
void delay100ms(void)   // error  0us
{
    
    unsigned char a,b,c;
    for(c=19;c>0;c--)
        for(b=20;b>0;b--)
            for(a=130;a>0;a--);
}

 
/* Timer T0 initialization */
void Timer0_Init()           
{
    
    TMOD &= 0x00;
    TMOD |= 0x01; // Timer T0 Set to mode 1
 
    TH0 = 0xff;   // Timing constant  0.1ms  Crystal vibration is 11.0592MHz
    TL0 = 0xa4;
 
    ET0 = 1;      
    TR0 = 1; 
		EA=1; 
	}
	
/*T0 Interrupt initialization */
void Time0_Init() interrupt 1 
{
     
	TR0=0;
	TH0 = 0xff; // 0.1ms
	TL0 = 0xa4;
	
	count++;
	if(count>100)
		{
    	
			count=0;
			if(DIR==1)
			{
    	
				value++;
				delay100ms();
			}
			if(DIR==0)
			{
    	
				value--;
				delay100ms();
			}
		}
		if(value==25)
		{
    	
			DIR=0;
		}
		if(value==5)
		{
    	
			DIR=1;
		}
		if(timer1>200)
		{
    	
			timer1=0;
		}
		if(timer1<value)
		{
    	
			PWM=1;
		}
		else
		{
    	
			PWM=0;
		}
		timer1++;
		TR0=1;
}
void main()
{
    
	Timer0_Init();
	while(1)
	{
    
		
		delay1s();
	}
}

Program 3

Use the key to control the angle , This is easy to implement , To control the angle, you only need to modify the program 1 in timer1 Value

// _nop_() Delay one machine cycle 
#include <reg52.h>
#include <intrins.h>
sbit PWM = P3^7;  // Set up PWM Output I/O port 
typedef unsigned int u16;
typedef unsigned char u8;
u8 count = 0;
u8 timer1;
u8 timer;
u16 n;
sbit k1=P3^1;// The angle increases 
sbit k2=P3^0;// The angle decreases 
/*  about 180° The steering gear  t = 0.5ms——————- The rudder turns  0 ° t = 1.0ms——————- The rudder turns  45° t = 1.5ms——————- The rudder turns  90° t = 2.0ms——————- The rudder turns  135° t = 2.5ms——————- The rudder turns 180 */

/* Delay program */
 void delay(u16 n)// One n Approximate delay 1ms
{
    
	u16 x,y;
	for(x=0;x<114;x++)
	for(y=0;y<n;y++);
}
void delay1s(void)   // error  0us
{
    
    unsigned char a,b,c;
    for(c=167;c>0;c--)
        for(b=171;b>0;b--)
            for(a=16;a>0;a--);
    _nop_();  //if Keil,require use intrins.h
}
/* Key scanner */
void keyscan()
{
    	
	if(k1==0)
	{
    	
		if(k1==0)
			delay(100);
		{
    
			timer+=5;
		}
		while(!k1);	
	}
	if(k2==0)
	{
    	
		if(k2==0)
			delay(100);
		{
    
			timer-=5;
		}
		while(!k2);	
	}


}



/* Timer T0 initialization */
void Timer0_Init()           
{
    
    TMOD &= 0x00;
    TMOD |= 0x01; // Timer T0 Set to mode 1
 
    TH0 = 0xff;   // Timing constant  0.1ms  Crystal vibration is 11.0592MHz
    TL0 = 0xa4;
 
    ET0 = 1;      
    TR0 = 1; 
	EA=1; 
	}
	
/*T0 Interrupt initialization */
void Time0_Init() interrupt 1 
{
    
	TR0 = 0; 
	TH0 = 0xff; // 0.1ms
	TL0 = 0xa4;
	
	if(count <= timer1) //5==0° 15==90°
	{
     
		PWM = 1; 
	}
	else 
	{
     
		PWM = 0; 
	}
	count++;
	if (count >= 200) //T = 20ms Zero clearing 
	{
     
		count = 0; 
	}
	TR0 = 1; // Turn on T0
}
void main()
{
    
	Timer0_Init();
	timer1=5;
	n=500;
	while(1)
	{
    
		keyscan();
		if(timer>25)
		{
    	
			timer=5;
		}
		timer1=timer;
		count=0;
		delay1s();
		timer1=5;
		count=0;
		delay1s();
	}
}