zero crossing signal problem

@ExperimenterUK,

In your circuit what is the opto-coupler IC number ? In other words, can you tell me the calculation how you have arrived at 15K 2W value ?

i have used moc3041...wat calculation u talkin abt sowie i dnt get u..?

i have made the exact circuit which is given in date datedheet of moc3041..chck it out...n i jst used 1/2w resistance for value 360ohm n 330ohms

My dear lucky6772, I am talking about ExperimenterUK's circuit which he had posted.Just see his circuit and tell me something about the 15k, 2w resistor.

sir i hvnt used that, i hv use which i hv posted..

@ExperimenterUK,
In your circuit what is the opto-coupler IC number ?

Amit Kumar Das

Well I'd use an H11B1, because they are very sensitive,
......and I have several
You could use many types as long as you supply enough current to turn them on at the right time.

can you tell me the calculation how you have arrived at 15K 2W value ?

Amit Kumar Das

15k is just a reasonable value.
It passes enough current to turn on many onto-couplers early in the cycle,
but not so much as to dissipate too much power.
A 15k resistor across 220 volts dissipates 3.22 watts.
This is only half wave so it dissipates 1.6 watts.

Some experimentation might be needed.

void isr(void) interrupt 0
{
delay(8);
moc=0; // bulb on
delay_100us():
moc=1; // triac is on now, switch off control
}

not working at all....the bulb stop glowin and remain off.///

Try ...

void isr(void) interrupt 0
{
delay(2); //also  try values of 1 to 8
moc=0; // bulb on
delay_100us():
moc=1; // triac is on now, switch off control
}

Can you post your circuit diagram.

#include <REG2051.H>
int i,j,a;
sbit up=P3^4;
sbit down=P3^5;
sbit moc=P3^7;
void delay();
/*void delay(int x)
{
for(i=0;i<100;i++)
for(j=0;j<x;j++)
;
} */
void delay1(int d)
{
int k;
TL0=0x17;
TH0=0xFC;
TR0=1;
for(k=0;k<d;k++) //will produce dx1ms of delay
{
while(TF0==0)
TF0=0;
TL0=0x17;
TH0=0xfc;
}
TR0=0;

}

void isr(void) interrupt 0
{
delay1(8);
moc=0; // bulb on
delay1(2);
moc=1; // triac is on now, switch off control
}
void main()
{
TMOD=0x01;
//P3=0xff;
//IT0 = 1; // Configure interrupt 0 for falling edge on /INT0 (P3.2)
EX0 = 1; // Enable EX0 Interrupt
EA = 1; // Enable Global Interrupt Flag
while(1)
{
P1=0xA5;
}

}

void delay1(int d) 
	{
		int k;
		TL0=0x17;
	    TH0=0xFC;
		TR0=1;
		for(k=0;k<d;k++)			  //will produce dx1ms of delay
		  {
			while(TF0==0)
			TF0=0;
			TL0=0x17;
			TH0=0xfc;
		  }
		  TR0=0;
		  
	}

s per my calculation the value "fc17" should produce 1milisecond of delay but it is not generting while i cheked on keil debugger its producing around 66ms. now tell me where i am wrong.