How to use STC89C52 microcontroller to make a multiple signal generator

First, paste the simulated circuit diagram below (the simulation software is Protuse, upload a larger diagram so that everyone can see it clearly):

Original parts list: STC89C52 microcontroller . Simulation requires these original parts. The specific hardware design is finalized and is being produced~

Upload the C program below~ (The IDE environment used is Keil 4, and the language is C language)

Source file (.c file):

1main.c file:

1 #include “reg52.h”

2 #include "init.h"

3 #include "single.h"

4 #include "delay.h"

5 #include "Key.h"

6 int main(void)

7 {

8 unsigned char Model=0;//0-square wave 1-triangular wave 2-sawtooth wave 3-sine wave

9 unsigned int Count=0;//Counter

10 unsigned int Squ_Per=256;

11 unsigned int Tri_Per=256;

12 unsigned int Saw_Per=256;

13 unsigned int Sin_Per=256;

14 init();

15 while(1)

16 {

17 while（Model==0）

18 {

19 Square_wave(Squ_Per,&Count);

20 Count+=4;

21 Squ_Per=Key_Plus(Squ_Per);

22 Squ_Per=Key_Subc(Squ_Per);

23 Model=Key_Model(Model, &Squ_Per, &Count);//Remember to restore the Period and Count data each time you exit the current while

twenty four }

25 while（Model==1）

26 {

27 Triangle_wave(Tri_Per,&Count);

28 Count+=4;

29 Tri_Per=Key_Plus(Tri_Per);

30 Tri_Per=Key_Subc(Tri_Per);

31 Model=Key_Model(Model,&Tri_Per,&Count);

32}

33 while（Model==2）

34 {

35 Sawtooth_wave(Saw_Per,&Count);

36 Count+=4;

37 Saw_Per=Key_Plus(Saw_Per);

38 Saw_Per=Key_Subc(Saw_Per);

39 Model=Key_Model(Model,&Saw_Per,&Count);

40}

41 while（Model==3）

42 {

43 Sin_wave(Sin_Per,&Count);

44 Count+=4;

45 Sin_Per=Key_Plus(Sin_Per);

46 Sin_Per=Key_Subc(Sin_Per);

47 Model=Key_Model(Model, &Sin_Per, &Count);

48 }

49 }

50 return 0;

51 }

2init.c file:

1 #include “reg52.h”

2 sbit CS_DAC=P1^5;//Chip select port of DAC0832

3 sbit WR_DAC=P1^6; //Data write port of DAC0832

4 extern void init(void)

5 {

6 P0=0xff;

7 P1=0xff;

8 P2=0xff;

9 P3=0xff;

10 CS_DAC=0;//The chip selects DAC0832, low level is active~

11 WR_DAC=0;//Write data to DAC0832

12}

3single.c file

1 #include “reg52.h”

2 #include "single.h"

3 #include "delay.h"

4 #define DATA P0

5 void Square_wave(unsigned int Per, unsigned int *Count)

6 {

7 if（*Count》=Per） *Count=0;

8 if(*Count

9 {

10 DATA=0x00;

11 }

12 else

13 {

14 DATA=0xFF;

15}

16}

17 void Triangle_wave(unsigned int Per, unsigned int *Count)

18 {

19 if（*Count》=Per） *Count=0;

20 if(*Count

twenty one {

22 DATA=*Count;

twenty three }

24 else

25 {

26 DATA=Per-*Count;

27}

28 }

29 void Sawtooth_wave(unsigned int Per, unsigned int *Count)

30 {

31 if（*Count》=Per） *Count=0;

32 if(*Count

33 {

34 DATA=*Count;

35}

36}

37 void Sin_wave(unsigned int Per, unsigned int *Count)

38 {

39 if（*Count》Per） *Count=0;

40 if(*Count

41 {

42 DATA=*Count;

43}

44 else if（*Count==Per/2）

45 {

46 delay(100);

47 }

48 else if(*Count

49 {

50 DATA=Per-*Count;

51 }

52 else if（*Count==Per）

53 {

54 delay(100);

55 }

56 }

4Key.c file:

1 #include "Key.h"

2 #include "delay.h"

3 sbit key2=P3^3; //wave Change

4 sbit key3=P3^4; //Fre plus

5 sbit key4=P3^5; //Fre subc

6 unsigned char Key_Model (unsigned char Model, unsigned int *Pre, unsigned int *Count)

7 {

8 if（key2==0）

9 {

10 delay(10);

11 if（key2==0）

12 {

13 Model=Model+1;

14 *Pre=256;

15 *Count=0;

16}

17}

18 while(key2==0);

19 if（Model》3）

20 {

21 Model=0;

twenty two }

23 return Model;

twenty four }

25 unsigned int Key_Plus (unsigned int Per)

26 {

27 if（key3==0）

28 {

29 delay(10);

30 if（key3==0）

31 {

32Per=Per+8;

33}

34}

35 while(key3==0);

36 if (Per》256)

37 {

38Per=0;

39 }

40 returnPer;

41 }

42 unsigned int Key_Subc (unsigned int Per)

43 {

44 if（key4==0）

45 {

46 delay(10);

47 if（key4==0）

48 {

49Per=Per-8;

50 }

51 }

52 while(key4==0);

53 if（Per《0）

54 {

55Per=256;

56 }

57 returnPer;

58 }

5delay.c file:

1 void delay(unsigned int r)

2 {

3 unsigned int i,j;

4 for（i=r;i》0;i--)

5 for（j=110;j》0;j--);

6}

Header file (.h file):

1init.h file:

1 extern void init(void);

2single.h file:

1 void Square_wave(unsigned int Per, unsigned int *Count);

2 void Triangle_wave(unsigned int Per, unsigned int *Count);

3 void Sawtooth_wave(unsigned int Per, unsigned int *Count);

4 void Sin_wave(unsigned int Per, unsigned int *Count);

3Key.h file:

1 #include “reg52.h”

2 unsigned char Key_Model(unsigned char Model, unsigned int *Pre, unsigned int *Count);

3 unsigned int Key_Plus(unsigned int Per);

4 unsigned int Key_Subc(unsigned int Per);

4delay.h file:

1 #include

2 void delay(unsigned int r);

3 #define NOP() _nop_()

I have uploaded all the project files used~ Let’s take a look at the simulation results: (You can perform filtering when designing the circuit, and then amplify the signal. In this case, the effect may be better~)

Square wave: Triangular wave: Sawtooth wave: Trapezoidal wave:

Please note that there is a small problem with the circuit. Due to my mistake, the output interfaces of Iout1 and Iout2 of DAC0832 should be connected as follows:

The areas that need to be modified are:

1. Change the power supply to dual power supply

2. The Iout interface needs to be grounded

After the modification is completed, the result will be more perfect. Upload a triangle wave waveform below.