99-minute countdown program with relay output

#include //Maximum 99 minutes countdown reminder

#define uchar unsigned char

#define uint unsigned int

sbit gewei0=P1^6; //Allow units digit display.

sbit shiwei0=P1^7; //Allow tens digit display.

sbit key1=P1^2; //Key 1, each press adds 10 minutes.

sbit key2=P1^1; //Key 2, each press adds 1 minute.

sbit key3=P1^0; //Key 3, start countdown or pause.

sbit beep=P1^3; //buzzer

sbit led=P1^4; //second indicator light

sbit jdq=P3^4; //relay

uchar k;

unsigned int s,m;

void delayms(uchar);

void delay(uint z);

void keyscan();

void display(uchar);

void init();

void xiang1();

void xiang2();

uchar code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};

void main()

{ init(); //Call "initialization".

while(1)

{ keyscan(); //Adjust "monitoring keys".

display(k); //Adjust "display".

}}

void keyscan() //Monitor keys.

{ if(key20)

{ delayms(26);

if(key20)

{ k++;

if(k>=99) //k==99 is consistent with the interrupt.

k=0;

while(!key2); //When key2 is released, the result of k+2 is displayed.

}

}

if(key10)

{ delayms(26);

if(key10)

{ k=k+10;

if(k>=99) //k99 is consistent with the interrupt.

k=0;

while(!key1);

}

}

if(key30)

{ delayms(26);

if(key3==0)

{

xiang1(); //Start the "countdown" prompt.

delayms(246);

TR0=~TR0;

jdq=~jdq; //Relay status flips with the start/stop button

while(!key3);

}}}

void delayms(uchar z) //delay.

{ uchar i,j;

for(i=z;i>0;i–)

for(j=110;j>0;j–); }

void delay(uint z)

{ while(z–); }

void display(uchar k) //Display.

{ uchar shi,ge;

shi=k/10;

ge = k%10;

gewei0=0;

P2=table[ge];

delayms(21);

gewei0=1;

shiwei0=0;

P2=table[shi];

delayms(21);

shiwei0=1;

}

void init() // Initialization. Set the interrupt and timer values.

{ TMOD = 0x01;

TH0=(65536-50000)/256; //Crystal oscillator 12MHz, timing 50ms.

TL0=(65536-50000)%256;

EA=1;

ET0=1;

}

void xiang1() //Timer starts prompt tone.

{undefined

uchar q;

for(q=0;q<100;q++)

{undefined

beep=0;

delayms(6);

beep=1;

delayms(4);

}

delayms(64);

}

void xiang2() //Timeout reminder sound – beep.

{undefined

unsigned int m;

uchar n,i;

for(i=3;i>0;i–)

{undefined

for(n=123;n>0;n–)

{undefined

beep=0;

delay(100);

beep=1;

delay(100);

}

for(m=3456;m>0;m–);

for(n=123;n>0;n–)

{undefined

beep=0;

delay(90);

beep=1;

delay(90);

}

1

for(m=56789;m>0;m–);

}

}

void time0()interrupt 1 //0 interrupt, interrupt number 1.

{ uint zxc=65432;

TH0=0xb1; //Crystal oscillator 12MHz, timing 20ms.

TL0=0xe0;

s++;

if(m25) //Indicate seconds.

{

m=0;

led = ~led;}

m++; //uchar m; defined as a global variable.

if(s3000) //3000×20ms=60000ms÷1000ms=60s(1 minute)

{ s=0; //Reset to zero. Wait for the next 1 minute.

k–; } //Countdown, minus 1 minute.

if(k<=0) //If it reaches 0, make a sound and turn off the interrupt.

{undefined

k=0;

xiang2();

TR0=0; //When the scheduled time is up, turn off interrupt 0 and stop.

jdq=1; //Relay release

}}