Homemade 51 MCU package library

The following contains: three files, main.c, gpoi.c, gpio.h

1 /*

2 * Main function

3 */

4

5 #include

6 #include

7

8 void main()

9

10 {

11 P2 = 0;

12 setBit(GPIO_2,3); //GPIO_2 means select P2 port, 3 means select P2.3 bit

13 while(1);

14 }

1 /*

2 *gpio.c file

3 */

4

5

6 #include

7 #include

8

9 void setBit(unsigned char gpio, unsigned char pin)

10 {

11 unsigned char i = 1;//0000 0001

12 i = i<

13 switch(gpio) //Select P0 P1 P2 P3

14 {

15 case 0:

16 P0 |=i;

17 break;

18 case 1:

19 P1 |=i;

20 break;

21 case 2:

22 P2 |=i;

23 break;

24 case 3:

25 P3 |=i;

26 break;

27

28 }

29 }

30 void resetBit(unsigned char gpio, unsigned char pin)

31 {

32 unsigned char i = 1; //0000 0001

33 i = i<

34 i = ~i;//reverse 1111 1011

35 switch (gpio)

36 {

37 case 0:

38 P0 &=i; //Bitwise AND operation requires two 1s to be 1 1111 1011 So the third bit is definitely 0, output low level

39 break;

40 case 1:

41 P1 &=i;

42 break;

43 case 2:

44 P2 &=i;

45 break;

46 case 3:

47 P3 &=i;

48 break;

49

50 }

51 }

1 /*

2 *gpio.h file

3 */

4

5 #ifndef _GPIO_H_

6 #define _GPIO_H_

7 // Enumeration 0 1 2 3 represents P0 P2 P3 P4

8 enum gpio{

9 GPIO_0 = 0, GPIO_1 = 1,

10 GPIO_2 = 2, GPIO_3 = 3

11 };

12 /*

13 *Set a pin to high level

14 *@param gpio: enumeration constant gpio

15 *@param pin: the pin number corresponding to each IO register

16 */

17

18 void etBit(

19 unsigned char gpio,

20 unsigned char pin);

twenty one

22 void resetBit(

23 unsigned char gpio,

24 unsigned char pin);

25 #endif