单片机20道复习题参考答案.doc

1.用P0 口驱动LED灯，要求循环左移，从右向左每次两个LED灯亮，程序重复

执行。【一个排线。排1（PO-LED）］

#include DelaylOms(SO); (

^include LED = LED « 2; unsigned char a, b;

void DelaylOms(unsigned int c); if (P0 == OxCO) for (;c>O;c-)

main() { {

{ LED = 0x03; for (b=38;b>0;b-) unsigned char LED; (

LED = 0x03; ) for (a=130;a>0;a~);

while (1) } )

{ } }

P0 = LED; void DelaylOm$(unsigned int c) }

2.用P0 口驱动LED灯做左右跑马灯程序，先向左侧跑马，每次左移2位，初始

时是2位LED灯亮，以后每次2个灯亮。待4次过后，再向右侧跑马，每次右移1位，初始时是1位LED灯亮，以后每次1个灯亮，执行8次。程序重

复执行。【一个排线。排1 (PO-LED)】

存include LED = LED « 2;P0 = LED;} (

ftinclude unsigned char a, b;

void DelaylOms(unsigned int c); 〃延时Delayl0ms(50); for (;c>0;c・・)

10ms LED = 0x80;P0 = LED; (

main。for(i=0;i<7;i++) for (b=38;b>0;b-)

( (Delayl0ms(50); ( unsigned char LED; LED = LED » l;P0 = LED; } for (a=130;a>0;a~);

unsigned char i; //Oxfe = llll 1110 }

LED = 0x03; Delayl0ms(50); }

while (1)

/

LED = OxO3;PO = LED; }

\

P0= LED; }

for(i=0;i<3;i*+) }

{Delayl0ms(50); void DelaylOms(unsigned int c)

flinclude

unsigned char Key_Scan()

i = 0;

include whil e

unsigned char keyValue = 0, i;

(K3==0))

sb it K2 = P1A 1; if (K1==O) K3 = P1A 2;

DelaylOms(l);

sb it K4 = P1A 3; DelaylOms(l); Adefi ne GPIO LED PO if (K1==O) void

main(void)

i = 0;

if

(K4==0)

while((i<50) && (K1==O))

unsigned char ledValue, keyNum; DelaylOms(l); ledValue = 0x01; DelaylOms(l)； if

(K4==0)

while (1)

if

keyValue = 4; keyNum = Key_Scan(); i = 0;

if (keyNum == 1)

while((i<50)&& (K4==0))

ledVal ue

if

(K2==0)

DelaylOms(l)； -CrorJIedValue,

DelaylOms(l);

if

keyValue = 1; ledVal ue

i = 0;

return keyValue;

_crolJledValue 1);

while((i<50)&& (K2==0))

void DelaylOms(unsigned int c)

else if (keyNum == 3)

DelaylOms(l);

unsigned char a, b; ledValue = Oxff;

for

(;c>O;c-)

else if (keyNum == 4)

for

(b=38;b>0;b-)

if

3. 用按键选择LED 灯做左右移动实验，3个按钮，K1对应P1.0, K2对应P1.1, K3

对应Pl.2, K1按下让LED 灯左移1位循环，K2按下让LED 灯右移1位循 环，K3按下，8个灯全亮。【两个排线。排1（PO-LED ）排2（P1-独立按键）】

I

void DelaylOms(unsigned int c); unsigned char Key_Scan();

if (K2==0)

else if (keyNum == 2)

keyValue = 2;

unsigned char a, b; for (;c>0;c ・・) (

for (b=38;b>0;b-) (

for (a=130;a>0;a-);

4. 单个静态数码管流动显示HELLO-LACo 【一个排线。排1(PO-・JP3(右上角))】

#lnclude

Wdefine GPIO_DIG PO void DelaylOms(unsigned int c); unsigned

char

code

DIG_CODE[10)={0x76,0x79,0x38,0x38,0x3f,0x4 0,0x38,0x77,0x39}; void main(void) (

unsigned char i = 0;

while(l)

GPIO_DIG = ~DIG_CODE[i]; i++； if(i == 10)

{

i = 0; }

Delayl0ms(50);

}

}

void Delayl0m$(unsigned int c)

5. 8位动态数码管显示BAD-FOODo 【两个排线。排1 (P0-LED)排2(P1-J16)

ttinclude #define GPIO_DIG P0 ^define GPIO.PLACE Pl

unsigned char code DIG_PLACE[8] = { 0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f}; unsigned char code DIG_CODE[8] {0x7c,0x77,0x5e,0x40,0x7L0x3f,0x3f,0x5e}; unsigned char Display Data (8); void DigDisplayO; void main(void) (

unsigned char i; for(i=0; i<8; i++)

(

DisplayData(i) = DIG_CODE(i];

} while(l) (

DigDisplayO;

}

}

void DigDisplay()

unsigned chari; unsigned int j; for(i=0; i<8; i++) (

GPIO_PLACE = DIG_PLACE[i] GPIO_DIG = DisplayData[i]; j = 10;

whlle(j-); GPIO_DIG = 0x00;

}

}