LPC2103 -Timer interrupt problem

dear all,

Please find the test code which i have tested .
Here at the first time when MRO maches it will give the interrupt and program will go to the ISR ,But when the second time MRO matches to TC it is not going to the ISR . One more thing which i noticed is that the IR register becomig high in 2nd time ,Still it is not going to the ISR

Is anybody faced this problem before ? Is their any mistakes which i have done here? Could any body enlight me for this problem

/**************************************************

Test APP- Timer 2

****************************************************/
#include<LPC2103.h>
void ISR(void);
int main(void)
{ int x=0;

T2PR = 0x00000005; //Load prescaler
T2TCR = 0x00000002; //Reset counter and prescaler
T2MCR = 0x00000003; //match reset the counter and generate an interrupt
T2MR0 = 0x00000010; //cycle time
T2TCR = 0x00000001; //enable timer

VICVectAddr4 = (unsigned)ISR; //Set the timer ISR vector address
VICVectCntl4 = 0x0000003A; //Set channel control

VICIntEnable |= 0x04000000; //Enable the TIMER2 interrupt

while(1)

{ x=x+1; //Keeps loop running in single step
}

}

void ISR (void)
{ T2IR = 0x0000000F; //Clear match 0 interrupt
}

dear all,

Please find the test code which i have tested .
Here at the first time when MRO maches it will give the interrupt and program will go to the ISR ,But when the second time MRO matches to TC it is not going to the ISR . One more thing which i noticed is that the IR register becomig high in 2nd time ,Still it is not going to the ISR

Is anybody faced this problem before ? Is their any mistakes which i have done here? Could any body enlight me for this problem

/**************************************************

Test APP- Timer 2

****************************************************/
#include<LPC2103.h>
void ISR(void);
int main(void)
{ int x=0;

T2PR = 0x00000005; //Load prescaler
T2TCR = 0x00000002; //Reset counter and prescaler
T2MCR = 0x00000003; //match reset the counter and generate an interrupt
T2MR0 = 0x00000010; //cycle time
T2TCR = 0x00000001; //enable timer

VICVectAddr4 = (unsigned)ISR; //Set the timer ISR vector address
VICVectCntl4 = 0x0000003A; //Set channel control

VICIntEnable |= 0x04000000; //Enable the TIMER2 interrupt

while(1)

{ x=x+1; //Keeps loop running in single step
}

}

void ISR (void)
{ T2IR = 0x0000000F; //Clear match 0 interrupt
}

void ISR (void) __irq
{ T2IR = 0x0000000F; //Clear match 0 interrupt
}

u have to add __irq to the isr function
u try this way u will get it.....

thanks for your reply ,

i just tried the way which you told ,but still i am getting the same answer ,It is going to ISR only once .

void isr(void) __irq;

void isr(void) __irq
{ }

u sure u didnt got?...then go to disassembly check whether the actual isr is loaded into the corresponding registers.

also it is better to enable timer after configuring the interrupt

thank you shameel,

i got it ,I just enabled the interrupt after configuring the interrupt .

thank alot for your help,

Thanks
Shanid
+91-8214003008

Here is the working code ,In ISR i have wrote one more line for writing an dummy to VECT.

/**************************************************

Test APP- Timer 2[Code which has worked ]

****************************************************/
#include<LPC2103.h>
void ISR(void);
int main(void)
{ int x=0;

T2PR = 0x00000005; //Load prescaler
T2TCR = 0x00000002; //Reset counter and prescaler
T2MCR = 0x00000003; //match reset the counter and generate an interrupt
T2MR0 = 0x00000010; //cycle time
T2TCR = 0x00000001; //enable timer

VICVectAddr4 = (unsigned)ISR; //Set the timer ISR vector address
VICVectCntl4 = 0x0000003A; //Set channel control

VICIntEnable |= 0x04000000; //Enable the TIMER2 interrupt

while(1)

{
x=x+1; //Keeps loop running in single step
}

}

void ISR (void) __irq
{

T2IR = 0x00000001; //Clear match 0 interrupt
VICVectAddr = 0x00000000; //Dummy write to signal end of interrupt

}

thanks