AT89C51 instant water heater program

Instantaneous water heater program MCU AT89C51 XAL 12MHz

//#pragma SRC 
#include  
#include  
#include  
void delay(unsigned int); //Delay function

void display(void); //display functionunsigned 
char keysCAN(void); //key scan processing functionvoid 
heatCTRl(void); //heating control functionvoid 
temptest(void); //temperature measurement functionsbit 
swkey=P1^0; //switch keysbit 
upkey=P1^1; //heating gear "+" keysbit 
downkey=P1^2; //heating gear "-" keysbit 
buzz=P1^05; //buzzer output 
terminalsbit triac=P1^6; //thyristor trigger signal output terminalsbit 
relay=P1^7; //relay control signal output terminalsbit 
LED1=P2^5; //heating gear indicator light 1 
sbit led2=P2^6; //heating gear indicator light 2 
sbit led3=P2^7; //heating gear indicator light 3 
signed char data ctemp; //current measured water temperature 
registerunsigned char data dispram[2]={0x10,0x10}; //display area 
cacheunsigned char data heatpower,px0count; //Heating gear register, external interrupt 0 counter 
bit tempov,t0tst,testok; //Over-temperature flag, temperature measurement start flag, temperature measurement completion flag 
/*---------------------------------------------- 
  Main function void main(void) 
  No parameters, no return valueCyclic 
  call display, key scan, temperature detection, heating control function 
----------------------------------------------*/ 
void main(void) 
{  
unsigned char i,j; 
ctemp=15; //Initialize water temperature register 
heatpower=5; //Initialize heating gear to 5 when 
tempov=0; //Clear over-temperature flag 
swkey=0; //Default switch key is pressed, enter standby state 
TMOD=0x11; //Set T0 and T1 working mode as 16-bit timer 
TCON=0x05; //Set external interrupt 0 and 1 to falling edge trigger 
IP=0x01; //Set external interrupt 0 priority 
IE=0x80; //Open total interruptwhile 
(1) 
  { 
  i=1; 
  do{ 
    for (j=0;j<100;j++) //Loop 100 times, about 0.5s 
      { 
      if (keyscan()) i=6; //If a key is pressed, display the current gear for 3s 
      display(); //Call the display function once for about 4ms 
      heatctrl(); //Call the heating control function 
      }//end for (b=0;b<100;b++) 
    temptest(); //Measure the temperature every 0.5s 
    } while (--i); //Determine whether to refresh the display by changing the size of the number of loops i 
  j=abs(ctemp); //Get the absolute value of the temperature 
  dispram[1]=j%10; //Get the ones digit and send it to the display 
  j/=10; //Get the tens digit 
  dispram[0]=j?j:0x11; //Send it to the display (with zero extinguishing) 
  }//end while (1) 
}  

/*-------------------------------------- 
  Delay function void delay(unsigned int dt) 
  Parameter: dt, no return value 
  Delay time = dt*500 machine cycles 
--------------------------------------*/ 
void delay(unsigned int dt) 
{ 
register unsigned char bt; //define register variable 
for (; dt; dt--) 
  for (bt=250; --bt; ); //This sentence is implemented as "DJNZ" when compiled, 250*2=500 machine cycles 
} 

/*-------------------------------------- 
  Display function void display(void) 
  no parameters, no return value 
  two-digit common anode digital tube scanning display 
--------------------------------------*/ 
void display(void) 
{ 
unsigned char code table[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,\ 
                            0x88,0x83,0xc6,0xa1,0x86,0x8e,0xbf,0xff}; 
unsigned char i,a; 
a=0xfe; //bit selection initial value 
for (i=0; i<2; i++) //loop scan two-digit digital tube 
  { 
  P2|=0x1f; //clear bit selection 
  P0=table[dispram[i]]; //send display segment code 
  P2&=a; //select one bit 
  delay(4); //delay 2ms 
  a=_crol_(a,1); //Change the bit selection word 
  P0=0xff; //Eliminate 
  } 
} 

/*---------------------------------------------------------- 
  Key scan processing function unsigned char keyscan(void) 
  No parameters, return value: unsigned character type, 0 if no key is pressed, other if a key is pressed 
  Affects global variables: heatpower 
----------------------------------------------------------*/ 
unsigned char keyscan(void) 
{ 
unsigned char i,ch; 
if (upkey==0) //"+" key 
  { 
  buzz=0; //Turn on the buzzer (make a key sound) 
  for (i=0;i<5;i++) display(); //Delay debounce 
  buzz=1; //Turn off the buzzerif 
  (heatpower<9) heatpower++; //Increase the gear position 
  dispram[0]=0; 
  dispram[1]=heatpower; //Display the current gearwhile 
  (upkey==0) display(); //Wait for the key to be releasedreturn 
  (1); //Return if a key is pressed 
  } 
  else if (downkey==0) //"-" key 
  { 
  buzz=0; //Turn on the buzzer (sound of a button press) 
  for (i=0;i<5;i++) display(); //Delay to eliminate bounce 
  buzz=1; //Turn off the buzzer 
  if (heatpower>0) heatpower--; //Minus one gear 
  dispram[0]=0; 
  dispram[1]=heatpower; //Display the current gear 
  while (downkey==0) display(); //Wait for the key to be released 
  return (2); //Return that a key has been pressed 
  } 
  else if (swkey==0) //Switch key 
  { 
  buzz=0; //Turn on the buzzer (sound of a button press) 
  for (i=0;i<30;i++) display(); //Delay to eliminate bounce 
  buzz=1; //Turn off the buzzer 
  swkey=1; //Set the switch key 
  while (swkey==0) display(); //Wait for the key to be released 
  ch=IE; //Temporarily store the interrupt control word IE 
  IE=0x00; //Disable interrupts 
  P0=0xff; 
  P1=0xff; 
  P2=0xff; //Clear port output 
  dispram[0]=0x10; 
  dispram[1]=0x10; //Display "--" 
  display(); 
  while (1) 
    { 
    while (swkey) display(); //Wait for the key to be pressedbuzz 
    =0; //Turn on the buzzer (make a key sound) 
    for (i=0;i<10;i++) display();//Delay debouncebuzz 
    =1; //Turn off the buzzerif 
    (swkey==0) break; //Confirm that the key is pressed 
    } 
  while (swkey==0) display(); //Wait for the key to be releasedIE 
  =ch; //Restore the interrupt control word IE 
  return (0); //Return that no key is pressed 
  } 
  else return (0); //Return when no key is pressed 
} 

/*-------------------------------------- 
  Heating control function void heatctrl(void) 
  No parameters, no return valueJudge 
  whether to heat, heating power and gear indicator light processing 
--------------------------------------*/ 
void heatctrl(void) 
{ 
if (!tempov) //When there is no over-temperature mark 
  { 
  relay=0; //Turn on the relaybuzz 
  =1; //Turn off the buzzerswitch 
  (heatpower) //Judge the heating gear 
    { 
    case 0: {EX1=0;ET1=0;triac=1;led1=1;led2=1;led3=1;break;}//0 gear does not heat, indicator light is not on 
    case 1: 
    case 2: 
    case 3: 
    case 4: {led1=0;led2=1;led3=1;EX1=1;break;} //1~4 gear No. 1 indicator is on 
    case 5: 
    case 6: 
    case 7: 
    case 8: {led1=0;led2=0;led3=1;EX1=1;break;} //5~8 gear No. 1, No. 2 indicator lights are on 
    case 9: {EX1=0;ET1=0;led1=0;led2=0;led3=0;triac=0;break;} //9 gear full power, indicator lights are all on 
    } 
  } 
  else //When there is an over-temperature mark 
  { 
  relay=1; //Disconnect the relayEX1 
  =0; ET1=0; triac=1; //Turn off the thyristorbuzz 
  =0; //Buzz alarm 
  } 
} 

/*-------------------------------------- 
  Temperature measurement function void temptest(void) 
  has no parameters, no return value, 
  affects global variables: ctemp, tempov 
  measures and calculates the temperature through table lookup to determine whether it is over-temperature 
--------------------------------------*/ 
void temptest(void) 
{ 
signed char temp,tempmin,tempmax; 
unsigned int t0rig; 
unsigned int code temptab[]={0x6262,0x61eb,0x6171,0x60f7,0x6047,0x5ff7,0x5f6e,0x5eef,0x5e53,0x5dbe,0x5d4b,0x5ca5,0x5c17,\ 
                             0x5b6b,0x5ada,0x5a5c,0x599b,0x58ff,0x5869,0x57b0,0x570d,0x5663,0x55c6,0x550e,0x5444,0x5396,\ 
                             0x52dd,0x5240,0x5189,0x50b0,0x500 5,0x4f20,0x4e69,0x4db1,0x4cef,0x4c42,0x4b64,0x4aaa,0x49e1,\ 
                             0x48fc,0x4847,0x476c,0x46b1,0x4604,0x4503,0x4449,0x4356,0x4299,0x41c0,0x40ce,0x3ff0,0x3f2b,\ 
                             0x3e33,0x3d86,0x3ca6,0x3bd2,0x3b 26,0x3a39,0x3973,0x38a6,0x37ef,0x373f,0x3687,0x35c3,0x3507,\ 
                             0x3487,0x33bc,0x32ed,0x324f,0x319e,0x3106,0x3053,0x2fa6,0x2f2a,0x2e88,0x2e00,0x2d63,0x2cd6,\ 
                             0x2c65,0x2bae,0x2b28,0x2a97,0x2a 07,0x298e,0x2914,0x287a,0x280d,0x278a,0x2703,0x2687 ,0x2626,\ 
                             0x25e5,0x256d,0x24ee,0x2489,0x2414,0x23bc,0x2356,0x22d9,0x2278,0x2203}; //Temperature frequency table 
px0count=2; //Frequency measurement interrupt function parameter 
t0tst=1; //Set frequency measurement program start flag 
EX0 =1; //Open the frequency measurement external interrupt 
testok=0; //Clear the frequency measurement program completion flag 
while (!testok) display(); //Wait for the test to complete 
t0rig=(unsigned int)TH0<<8|TL0; / /byte synthesis word 
tempmin=0; //The following is the binary table lookup method to calculate the temperature value 
tempmax=100; //tempmin and tempmax are the range of the temperature table 
while (1) 
  { 
  temp=(tempmax+tempmin)/2; / /Assume that the current temperature is the midpoint between the maximum and minimum values 
  ​​if (t0rig==temptab[temp]) break; //If the actual value is equal to the assumed value, end the search 
    else if (t0rig>temptab[temp]) tempmax=temp; //If the actual value is greater than the assumed value, reduce the maximum value of the search range 
    else tempmin=temp; //If the actual value If the search range is smaller than the assumed value, increase the minimum value of the search range 
  if (tempmax-tempmin<=1) //If the search range has been narrowed to 1 degree, 
    { //Judge which endpoint the actual value is closer to 
    if (temptab[tempmax]+ temptab[tempmin]>2*t0rig) temp=tempmax;//Close to the maximum value, take the maximum value 
      else temp=tempmin; //Close to the minimum value, take the minimum value 
    break; //End the search 
    } 
  } 
ctemp=temp; //Refresh the current Temperature register 
if (temp>65) tempov=1; //If the temperature exceeds 65 degrees, set the over-temperature flag 
  else if (temp<45) tempov=0; //When the temperature drops below 45 degrees, clear the over-temperature flag 
} 

/*------------------------------------------ 
  Temperature measurement frequency test function void tempFrequency(void) 
  uses external X0 interrupt and register bank 1 
  to measure the temperature - the frequency of the frequency conversion circuit 
---------------------------- --------------*/ 
void tempfrequency(void) interrupt 0 using 1 
{ 
if (--px0count) return; //Find the starting point or count 
if (t0tst) //If it is the starting point 
  { 
  t0tst=0; //Clear the frequency measurement start flag 
  px0count=100; //Take 100 square waves as one frequency measurement 
  TH0=0; 
  TL0=0; //Clear timer T0 
  TR0=1; //Start timing 
  } 
  else //If it is the end point 
  { 
  TR0=0; //Stop timing 
  EX0=0; //Stop frequency measurement external interrupt 
  testok=1; //Set frequency measurement completion flag 
  } 
} 

/*--------- ----------------------------- 
  Heating control over-zero detection function void pass0(void) 
  uses external X1 interrupt, register group 2 
  detects over 0 o'clock, assign initial value to timer T1 
--------------------------------------*/ 
void pass0(void) interrupt 2 using 2 
{ 
unsigned char code powertab[]={0xd8,0xf0,0xe2,0x63,0xe5,0x25,0xe8,0x3e,0xeb,0x16,0xed,0xda,0xf0,0xb2,0xf3,0xcb,0xf7,0x8d,0xf7,0x8d}; //10 power levels of thyristor conduction angle delay parameter table 
TH1=powertab[2*heatpower]-1; 
TL1=powertab[2*heatpower+1]; //After the mains passes zero, assign delay parameters to timer T1 according to the currently set gear 
ET1=1; //Allow timer T1 interrupt 
TR1=1; //Turn on timer T1 
} 

/*------------------------------------------ 
  thyristor trigger signal control function void tria CC trl(void) 
  uses timer T1 interrupt, register group 3 
  sends trigger signal to thyristor 
------------------------------------------*/ 
void triacctrl(void) interrupt 3 using 3 
{ 
register unsigned char i; 
triac=0; //output thyristor conduction signal 
ET1=0; //turn off timer T1 interrupt 
TR1=0; //stop timer operation 
for (i=0;i<2;i++); //delay to ensure that the conduction signal has enough width 
triac=1; //complete thyristor conduction signal 
}