单片机驱动电机

直流电机：

其实直流电机也就是小的时候玩的四驱车的马达，但是在单片机驱动是，需要家驱动电路，我至今还没驱动起直流电机，就是因为目前不知道怎么来连接驱动电路；

控制直流电机的转速的是用PWM波形来控制，就是控制高电平持续时间在一个周期中所占的比例，这个有个专用的名词叫占空比来着

用单片机得到PWM波形有三种方式

方式1：利用软件延时，当高电平延时时间到时的时候，对I/O口电平取反，然后咋延时，当低电平延时时间到后，在对I/O口进行取反，如此循环就得到PWM波形

方式2：利用的是定时器延时，控制方法同上

方式3：利用单片机自带的PWM控制器

示例代码：得到PWM波形

//利用软件延时：并且用键盘扫描得到不同的PWM

#include

#define uint unsigned int

#define uchar unsigned char

sbit PWN = P1^1;

sbit key1 = P3^1;

sbit key2 = P3^2;

uchar num;

uint yanshi;

uchar code table[]={0xc0,0xf9,0xa4,0xb0,

0x99,0x92,0x82,0xf8,

0x80,0x90,0x88,0x83,

0xc6,0xa1,0x86,0x8e};

void delayms(uint z)

{

uint x,y;

for(x = z;x>0;x--)

for(y=110;y>0;y--);

}

void main()

{

while(1)

{

P3 = 0xff;

if(key1 ==0)

{

delayms(2);

if(key1 ==0)

{

while(!key1);

num++;

if(num ==7)

{

num =0;

}

yanshi = 200*num;

}

}

switch(num)

{

case 1:

{

PWN = ~PWN;

P0 = table[num];

delayms(yanshi);

}

break;

case 2:

{

PWN = ~PWN;

P0 = table[num];

delayms(yanshi);

}

break;

case 3:

{

PWN = ~PWN;

P0 = table[num];

delayms(yanshi);

}

break;

case 4:

{

PWN = ~PWN;

P0 = table[num];

delayms(yanshi);

}

break;

case 5:

{

PWN = ~PWN;

P0 = table[num];

delayms(yanshi);

}

break;

case 6:

{

P0 = table[num];

PWN = 1;

}

break;

}

}

}

示例代码2：

#include

#define uint unsigned int

#define uchar unsigned char

#define TIME 600

sbit led1 = P1^1;

void delay(uint xx)

{

while(xx--);

}

void main()

{

uint x;

while(1)

{

for(x = 0;x

{

led1 = 0;

delay(TIME-x);

led1 = 1;

delay(x);

}

delay(65535);

for(x=TIME;x>0;x--)

{

led1 = 0;

delay(TIME-x);

led1 = 1;

delay(x);

}

}

}

步进电机：

步进电机是将电脉冲信号转变为角位移和线位移的开环控制元件，在非超载的情况下，电机的转速，停止的位置，只取决于脉冲信号的频率数，和脉冲数，而不受负载变化的影响

基本的步进电机的驱动程序：

#include

#define uint unsigned int

main()

{

uint i,j;

while(1)

{

P1 = 0x01;//0000 0001

for(i = 0;i<800;i++);

P1 = 0x02;//0000 0010

for(i = 0;i<800;i++);

P1 = 0x04;//0000 0100

for(i = 0;i<800;i++);

P1 = 0x08;//0000 1000

for(i = 0;i<800;i++);

}

}

综合程序；用按键实现步进电机的启动，停止，增速，减速，并在数码管上显示出来：

#include

#define uint unsigned int

#define uchar unsigned char

sbit dula = P2^7;

sbit wela = P2^6;

sbit key1 = P3^3;//这里是解决我的单片机上按键坏掉的问题

sbit key2 = P2^4;

sbit key3 = P2^5;

sbit key4 = P2^1;

uchar aa,flag,speed,flag1,i;//flag 是用来标记启动和停止的标志位

//flag1 是用来标记正转还是反转的标志位

uchar code table[]={0x01,0x02,0x04,0x08};

uchar code table1[]={0x3f,0x06,0x5b,0x4f,

0x66,0x6d,0x7d,0x07,

0x7f,0x6f,0x77,0x7c,

0x39,0x5e,0x79,0x71};

void init()

{

TMOD = 0x01;

TH0 = (65536-2400)/256;

TL0 = (65536-2400)%256;

EA = 1;

ET0 = 1;

}

void delay(uint z)

{

uint x ,y;

for(x = z;x>0 ;x--)

for(y = 110 ;y>0;y--);

}

void display1()//on显示函数

{

wela = 1;

P0 = 0xf7;

wela = 0;

P0 = 0;

dula = 1;

P0 = 0x3f;

dula = 0;

delay(5);

P0 = 0xff;

wela = 1;

P0 = 0xef;

wela =0;

P0 = 0;

dula = 1;

P0 = 0x54;

dula = 0;

delay(5);

}

void display2()//off显示函数

{

wela = 1;

P0 = 0xf7;

wela = 0;

P0 = 0;

dula = 1;

P0 = 0x3f;

dula = 0;

delay(5);

P0 = 0xff;

wela = 1;

P0 = 0xef;

wela =0;

P0 = 0;

dula = 1;

P0 = 0x71;

dula = 0;

delay(5);

wela = 1;

P0 = 0xdf;

wela = 0;

P0 = 0;

dula = 1;

P0 = 0x71;

dula = 0;

delay(5);

P0 = 0xff;

}

void display()//显示函数

{

uchar gw,sw;

gw = speed%10;

sw = speed/10;

wela = 1;

P0 = 0xfe;

wela = 0;

P0 = 0;

dula = 1;

P0 = table1[sw];

dula = 0;

delay(5);

P0 = 0xff;

wela = 1;

P0 = 0xfd;

wela =0;

P0 = 0;

dula = 1;

P0 = table1[gw];

dula = 0;

delay(5);

}

void key_scan()//键盘扫描函数

{

P3 = 0xff;

if(key2==0)

{

delay(5);

if(key2==0)

{

while(!key2)

{