Analysis of the problems of the 10th Blue Bridge Cup single chip microcomputer provincial competition

Don't talk much , Let's take a look at the 10th （2019） Your topic .

subject

 

 

 

  The topic of this time is still three modules （ Nixie tube 、LED、 Key ）, Also used. ADC、DAC、NE555, except NE555 I haven't seen it before , Others are also common peripherals , As long as you have practiced , It's not difficult , The most important thing is programming logic . 

1 The nixie tube shows

The nixie tube has a voltage measurement interface and a frequency measurement interface .

2 LED

The interface is voltage measurement interface L1 bright , Frequency measurement interface L2 bright , Voltage in [1.5,2.5) perhaps >=3.5V when L3 bright , Frequency at [1k,5k) perhaps >=10k when L4 bright , When a fixed voltage is output L5 destroy , otherwise L5 bright .

3 Key module

Using separate keys ,s4 It is the switching between voltage measurement interface and frequency measurement interface ,s5 yes DAC Fixed output voltage or DAC The output changes with the output voltage of the voltmeter ,s6 yes LED The switch of ,s7 It is the switch of digital tube display .

4 NE555

NE555 Just use two timers , One for counting , One for timing . Among them, timing 1ms Look at how many counts are recorded , turn RB3, The frequency will change .

5 ADC

Is to rewrite the underlying driver code （IIC）.

6 DAC

Is to rewrite the underlying driver code （IIC）.

IIC.c

#include"IIC.h"

#define DELAY_TIME 5

#define SlaveAddrW 0xA0
#define SlaveAddrR 0xA1

sbit SDA = P2^1; 
sbit SCL = P2^0; 

void IIC_Delay(unsigned char i)
{
    do{_nop_();}
    while(i--);        
}

void IIC_Start(void)
{
    SDA = 1;
    SCL = 1;
    IIC_Delay(DELAY_TIME);
    SDA = 0;
    IIC_Delay(DELAY_TIME);
    SCL = 0;	
}

void IIC_Stop(void)
{
    SDA = 0;
    SCL = 1;
    IIC_Delay(DELAY_TIME);
    SDA = 1;
    IIC_Delay(DELAY_TIME);
}

bit IIC_WaitAck(void)
{
    bit ackbit;
	
    SCL  = 1;
    IIC_Delay(DELAY_TIME);
    ackbit = SDA;
    SCL = 0;
    IIC_Delay(DELAY_TIME);
    return ackbit;
}

void IIC_SendByte(unsigned char byt)
{
    unsigned char i;

    for(i=0; i<8; i++)
    {
        SCL  = 0;
        IIC_Delay(DELAY_TIME);
        if(byt & 0x80) SDA  = 1;
        else SDA  = 0;
        IIC_Delay(DELAY_TIME);
        SCL = 1;
        byt <<= 1;
        IIC_Delay(DELAY_TIME);
    }
    SCL  = 0;  
}

unsigned char IIC_RecByte(void)
{
    unsigned char i, da;
    for(i=0; i<8; i++)
    {   
    	SCL = 1;
	IIC_Delay(DELAY_TIME);
	da <<= 1;
	if(SDA) da |= 1;
	SCL = 0;
	IIC_Delay(DELAY_TIME);
    }
    return da;    
}

unsigned char Read_AD()
{
	unsigned char temp;
	
	IIC_Start();
	IIC_SendByte(0x90);
	IIC_WaitAck();
	
	IIC_SendByte(0x03);
	IIC_WaitAck();
	IIC_Stop();
	
	IIC_Start();
	IIC_SendByte(0x91);
	IIC_WaitAck();
	temp=IIC_RecByte();
	IIC_Stop();
	
	return temp;
}

void DA_out(unsigned char date)
{
	IIC_Start();
	IIC_SendByte(0x90);
	IIC_WaitAck();
	IIC_SendByte(0x40);
	IIC_WaitAck();
	IIC_SendByte(date);
	IIC_WaitAck();
	IIC_Stop();
}

IIC.h

#ifndef _IIC_H_
#define _IIC_H_

#include<stc15f2k60s2.h>
#include<intrins.h>

void IIC_Delay(unsigned char i);
void IIC_Start(void);
void IIC_Stop(void);
bit IIC_WaitAck(void);
void IIC_SendByte(unsigned char byt);
unsigned char IIC_RecByte(void);
unsigned char Read_AD();
void DA_out(unsigned char date);

#endif

init.c

#include"init.h"

#define u8 unsigned char
#define u16 unsigned int
#define state_0 0
#define state_1 1
#define state_2 2

static u8 key_state,key_num,key_press,segadder;
u8 value=0;
extern bit mode,tube;
extern u8 a;

u8 code tab[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0xbf,0xff,0xc1,0xce};
u8 seg[]={11,11,11,11,11,11,11,11};

void all_init()  // Turn off irrelevant peripherals 
{
	P2=(P2&0x1f)|0x80;P0=0xff;P2&=0x1f;
	
	P2=(P2&0x1f)|0xa0;P04=0;P06=0;P2&=0x1f;
	
	P2=(P2&0x1f)|0xc0;P0=0x00;P2&=0x1f;
	
	P2=(P2&0x1f)|0xe0;P0=0xff;P2&=0x1f;
}

void display()   // Nixie tube display function 
{
	P2=(P2&0x1f)|0xe0;P0=0xff;P2&=0x1f;
	
	P2=(P2&0x1f)|0xc0;P0=1<<segadder;P2&=0x1f;
	
	P2=(P2&0x1f)|0xe0;
	if((a==1||mode==0)&&segadder==5&&tube==1)
		P0=tab[seg[segadder]]&0x7f;
	else
		P0=tab[seg[segadder]];
	P2&=0x1f;
	
	if(++segadder==8)segadder=0;
}

u8 Read_key()   // Independent keyboard 
{
	key_press=P3&0x0f;
	switch(key_state)
	{
		case state_0:
			if(key_press!=0x0f)
				key_state=state_1;
		break;
		case state_1:
			if(key_press!=0x0f)
			{
				if((key_press & 0x08)==0) key_num=4;
				if((key_press & 0x04)==0) key_num=5;
				if((key_press & 0x02)==0) key_num=6;
				if((key_press & 0x01)==0) key_num=7;
				key_state=state_2;
			}
			else
				key_state=state_0;
		break;
		case state_2:
			if(key_press==0x0f)
				key_state=state_0;
		break;
	}
	value=key_num;
	key_num=0;
	return value;
}

void Timer1Init(void)		// Timer 1 timing 1ms
{
	AUXR |= 0x40;		
	TMOD &= 0x0F;	
	TL1 = 0xCD;	
	TH1 = 0xD4;	
	TF1 = 0;		
	TR1 = 1;
  EA = 1;
  ET1 = 1;	
}

void Timer0Init(void)  // Timer 0  Switch to counting mode 
{
		TMOD = 0x04;    
		TL0 = 0;
		TH0 = 0;
		TF0 = 0;
		TR0 = 1;
		ET0 = 1;
}

init.h

#ifndef _INIT_H_
#define _INIT_H_

#include<stc15f2k60s2.h>

void all_init();
void display();
unsigned char Read_key();
void Timer1Init(void);
void Timer0Init(void);


#endif

jm.c

#include"jm.h"

#define u8 unsigned char
#define u16 unsigned int
	
extern bit mode,v,led,tube;    // extern Indicates that this variable is defined elsewhere , To quote... Here 
extern u8 seg[];
extern u16 F,RB2;

void jm4()
{
	if(mode==0)
		jm5();    // Voltage measurement interface 
	else          // Frequency measurement interface 
	{
		seg[0]=13;
		seg[1]=11;
		seg[2]=11;
		if(F/10000!=0)
		{
			seg[3]=F/10000;
			seg[4]=F/1000%10;
			seg[5]=F/100%10;
			seg[6]=F/10%10;
			seg[7]=F%10;
		}
		else if(F/1000!=0)     
		{
			seg[3]=11;       // The unused nixie tube goes out 
			seg[4]=F/1000;
			seg[5]=F/100%10;
			seg[6]=F/10%10;
			seg[7]=F%10;
		}
		else if(F/100!=0)
		{
			seg[3]=11;
			seg[4]=11;
			seg[5]=F/100;
			seg[6]=F/10%10;
			seg[7]=F%10;
		}
		else
		{
			seg[3]=11;
			seg[4]=11;
			seg[5]=11;
			seg[6]=F/10;
			seg[7]=F%10;
		}
	}
}

void jm5()
{
	if(v==0)
	{
		seg[0]=12;
		seg[1]=11;
		seg[2]=11;
		seg[3]=11;
		seg[4]=11;
		seg[5]=2;
		seg[6]=0;
		seg[7]=0;
	}
	else if(v==1)
	{
		seg[0]=12;
		seg[1]=11;
		seg[2]=11;
		seg[3]=11;
		seg[4]=11;
		seg[5]=RB2/100;
		seg[6]=RB2/10%10;
		seg[7]=RB2%10;
	}
}

void jm6()   //LED function 
{
	u8 i=0xff;
	if(led==1)
	{
		if(mode==0)
		{
			P2=(P2&0x1f)|0x80;P0=0xfe;P2&=0x1f;
		}
		else
		{
			P2=(P2&0x1f)|0x80;P0=0xfd;P2&=0x1f;
		}
		if((RB2>=150&&RB2<250)||(RB2>350))
		{
			P2=(P2&0x1f)|0x80;P02=0;P2&=0x1f;
		}
		else
		{
			P2=(P2&0x1f)|0x80;P02=1;P2&=0x1f;
		}
		if((F>=1000&&F<5000)||(F>=10000))
		{
			P2=(P2&0x1f)|0x80;P03=0;P2&=0x1f;
		}
		else
		{
			P2=(P2&0x1f)|0x80;P03=1;P2&=0x1f;
		}
		if(v==1)
		{
			P2=(P2&0x1f)|0x80;P04=0;P2&=0x1f;
		}
		else
		{
			P2=(P2&0x1f)|0x80;P04=1;P2&=0x1f;
		}
	}
	else
	{
		P2=(P2&0x1f)|0x80;P0=0xff;P2&=0x1f;
	}
}

void jm7()    // Nixie tube switch function 
{
	if(tube==0)
	{
		seg[0]=11;
		seg[1]=11;
		seg[2]=11;
		seg[3]=11;
		seg[4]=11;
		seg[5]=11;
		seg[6]=11;
		seg[7]=11;
	}
	else
		jm4();
}

jm.h

#ifndef _JM_H_
#define _JM_H_

#include<stc15f2k60s2.h>

void jm4();
void jm5();
void jm6();
void jm7();

#endif

main.c

#include"init.h"
#include"IIC.h"
#include"jm.h"

#define u8 unsigned char
#define u16 unsigned int
	
u8 num=0,a=0,b=0;
u16 RB2_count=0,F_count=0,F=0,RB2=0;
bit mode=0,v=0,led=1,tube=1,F_flag=0,RB2_flag=0;

void main()
{
	all_init();
	Timer1Init();
	Timer0Init();
	while(1)
	{
		num=Read_key();
		switch(num)
		{
			case 4:
				mode^=1;
			  a=0;
			break;
			case 5:
				v^=1;
				a=1;
			break;
			case 6:
				led^=1;
			  b=0;
			break;
			case 7:
				tube^=1;
			jm7();
			break;
		}
		if(a==0&&tube==1)jm4();
		if(a==1&&tube==1)jm5();
		if(b==0)jm6();
		if(F_flag==1)    // Calculate the frequency 
		{
			F_flag=0;	
			TR0=0;
			F=TH0*256+TL0;
			TL0=0;
			TH0=0;
			TR0=1;
		}
		if(RB2_flag==1)
		{
			RB2_flag=0;
			RB2=Read_AD();
			if(v==0)DA_out(102.4);   //DAC Output 
			else DA_out(RB2);		
			RB2=(RB2*100)/51.0+0.5;
		}
	}
}

void Timer1() interrupt 3
{
	display();
	if(++RB2_count==500)
	{
		RB2_count=0;
		RB2_flag=1;
	}
	if(++F_count==1000)
	{
		F_count=0;
		F_flag=1;
	}
}