alarm clock problem

[energetic007]

hey, i want to design a pic based alarm clock but firstly i need to get familiar with the timing issues and rtc concepts.. i have learnt how to configure the timers i.e. TMR0,TMR1,TMR2 of f877a. But my problem is that i am not able to guess that.. what do we do when we set the time e.g. say on our phones we set alarm at 5AM .. or say a timer for 20 minutes ... i am feeling very confused regarding what do we actually set there ... is it the number of counts after which the timer should interrupt the processor or what else also if that is the case then how can i design a timer that obey the keys .

can someone provide me a working code that has the provision for increasing or decreasing the timing with buttons.
my code does not respond when i press the button.
its been three months since i am stuck in this code and haven't finished a single project because i am feeling very depressed due to my very little understanding of the subject .
////////////////////////////////////////////////////////////////////////////////////

#include<16f877a.h>
#fuses NOCPD,NOWDT,XT
#use delay(clock=4m)
#byte T2CON=0x12
int16 count=0;
int16 count_1=0;
#INT_TIMER2
void isr(void)
{
count++;
if(count==15) // 65.536ms x 15=1000ms = 1 second/ tick
{
count=0;
count_1++;
if(count_1==5) //for 5 sec delay
{ count_1 =0;
output_toggle(PIN_A3); // led toggles at a rate of 1second .
}
}
}

void main()
{
output_a(0x00);
setup_adc(ADC_OFF);
setup_comparator(NC_NC_NC_NC);
setup_psp(PSP_DISABLED);
setup_timer_2(T2_DIV_BY_16,255,16); // 1usx16= 16us x 256 =4096 us x 16= 65536us= 65.536 ms delay
enable_interrupts(GLOBAL);
enable_interrupts(INT_TIMER2);
do
{ output_high(PIN_C3);
if (input(PIN_C0)==0) // button is here.
count_1=10; // for 10 sec delay
}
while(1==1);
}
/////////////////////////////////////////////////////////////////////////////////

[asmboy]

code buttons?

[Mike Walne]

Take a step back.

1) What are expecting your code to do?
2) How do your LEDs tell you what's going on?
3) Do you have an RS232 link to a PC?
4) Which CCS samples have you tried and tested?

Mike

PS

Indent your code and use the code button to make it easier to follow.

[energetic007]

@ asmboy :
code buttons means : on each button press the timer value gets increased by a certain multiple.
e.g. let the counter interrupt the processor after 10 second on first press.
on second press the timer interrupts the processor after 20seconds.
on third press the timer interrupts the processor after 30 seconds.
and so on.
so if i want to take a quick nap of 15 minutes , i set the timer to interrupt after 15 minutes.
sorry, for the exaggeration but this is what i really want to do.

@ MIKE
1) i want to design a timer that times out after a fixed amount of time and rings a bell or does something
2) my led at port A pin A3 toggles at a rate as fixed by the program e.g. it toggles here at a rate of 1 second.
3) no, i don't have a RS232 link.
4) sorry, i couldn't get your last question .

[Mike Walne]