REAL TIME OPERATING SYSTEMS

AIM:

            To write a java program for real-time program for implementing an alarm clock shall be developed

ALGORITHM:

Step 1:         Start the program

Step 2:         Display init is used for initialization, and shall be called from the main function of the program.

Step 3:         Before the processes are created.

Step 4:         Display time displays the current time, and shall be called by the clock process

Step 5:         Display alarm time shows the current alarm time, and shall be called when a new alarm time is set.

Step 6:         Erase alarm time erases the displayed alarm time, and shall be called when the user acknowledges an alarm

Step 7:         Display alarm text is used to show an alarm activation, and shall be called when the user shall be informed that the alarm has been activated

Step 8:         When the alarm is activated the first time, and when the alarm is activated repeatedly (which is every 10 seconds, according to the above stated requirements).

Step 9:         End of programs

PROGRAM

#include<stdio.h>

#include<conio.h>

#include<dos.h>

struct clk

{

int hh,mm,ss;

}c1,c2;

void clock(int *h1,int *m1,int *s1)

{

*s1=*s1+1;

if(*s1==60)

{

*s1=0; *m1=*m1+1;

if(*m1==60)

{

*m1=0;*h1=*h1+1;

if(*h1==24)

*h1=0;

}

}

}

void timer(int *h,int *m,int *s)

{

if((*s)!=0)

{

*s=*s-1;

}

else if((*s)==0)

{

if(*m!=0)

{

*s=59;*m=*m-1;

}

else if(*m==0)

{

if(*h!=0)

{

*m=59;*h=*h-1;

}

}

}

}

void alarm()

{

int i;

while(!kbhit())

{

for(i=0;i<2;i++)

{

sound(5000);

delay(100);

nosound();

delay(200);

}

delay(500);

}

}

void main()

{

char ch;

struct time t;

clrscr();

printf("\nPress:-\n\tA: for alarm Clock\n\tT: for Timer\n");

printf("\Enter your Choice:");

ch=getche();

switch (ch)

{

case 'A':

case 'a':

{

printf("\n\n\n24 hr Format(HH:MM:SS)");

gettime(&t);

c1.hh=t.ti_hour; c1.mm=t.ti_min; c1.ss=t.ti_sec;

printf("\nEnter alarm time : ");

scanf("%d:%d:%d",&c2.hh,&c2.mm,&c2.ss);

if(c2.hh>24||c2.mm>60||c2.ss>60)

{

printf("\n\n\tERROR: Invalid time.\n\tRestart the program.");

delay(2500);exit(0);

}

while((c1.ss!=c2.ss)||(c1.hh!=c2.hh)||(c1.mm!=c2.mm))

{

clrscr();

printf("\n\nAlarm time: %02d:%02d:%02d\n",c2.hh,c2.mm,c2.ss);

printf("\nCurrent Time: %02d:%02d:%02d",c1.hh,c1.mm,c1.ss);

clock(&c1.hh,&c1.mm,&c1.ss);

delay(1000);

};

clrscr();printf("\n\n\n\n\t\t\t\tAlarm time reached\n\n\t\t\t\tPress any to Exit.");

alarm();

exit(0);

}

break;

case 'T':

case 't':

{

printf("\n\n\nEnter time for timer (HH:MM:SS): ");

scanf("%d:%d:%d",&c1.hh,&c1.mm,&c1.ss);

while(c1.hh>0||c1.mm>0||c1.ss>0)

{

clrscr();

printf("The Current Time:\n");

printf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\t\t\t\t");

printf("%02d:%02d:%02d",c1.hh,c1.mm,c1.ss);

timer(&c1.hh,&c1.mm,&c1.ss);

delay(1000);

}

clrscr();

printf("\n");

printf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\t\t\t\t");

printf("00:00:00");

alarm();

exit(0);

}

break;

default:

{

printf("\n\tInvalid Input\n\n\tPlease restart the program");

delay(2500);exit(0);

}

}

}