Posted on May 17, 2011 at 09:37Hai all,
In my code for RTC periodic interrupt, the ISR is becomming reentrant. in the execution profile i've observed that thte VIC1->VAR register is not resetting after the assaignment. My code is:
#include
void CMP_Configuration(void);
__irq void RTC_ISR(void);
u8 k=0;
vu32 tmp;
void main()
{
u8 d=0x00;
#ifdef DEBUG
debug();
#endif
CMP_Configuration();
while(1)
{
if (k==1)
{
k=0;
GPIO7->DR[0x3FC] = ~d;
}
}
}
/********************************Subroutines******************************/
void CMP_Configuration(void)
{
/********************* VIC Configuration******************************/
VIC1->VAiR[0] = (unsigned int)RTC_ISR; // Interrupt vector address = ISR
VIC1->INTSR = 0x00; // RTC interrupt is IRQ type
VIC1->VCiR[0] = 0x28; // RTC interrupt configured at 0 priority
VIC1->INTER |= 0x0100; // RTC interrupt enabled.
/*************************RTC Configuration***************************/
RTC->CR |= 0x80; // Write enable date, time and milli second registers
RTC->DTR = 0x20070202; // Date initialization
RTC->TR = 0x12154552; // Time initialization
RTC->MILR = 0x00000000; // Milli Second Initialization
RTC->CR &= ~0x80; // Write disable date, time and milli second registers
RTC->CR = 0x00240000; // 128Hz Periodic interrupt selected
tmp = RTC->SR; // Clear RTC Periodic Interrupt Flag
/*************************GPIO7 Configuration****************************/
GPIO7->DDR |= GPIO_Pin_All; // All pins in GPIO7 are o/p pins
SCU->GPIOOUT[0x07] = 0x5555;//O/pis of general purpose type(alternate o/p1)
SCU->GPIOTYPE[0x07]= 0X0000; // All pins are of push-pull type
SCU->GPIOIN[7] = 0x0000; // IP connection disabled.
}
__irq void RTC_ISR(void)
{
k=1;
tmp = RTC->SR; // clear RTC Periodic Interrupt flag
VIC1->VAR=0; // dummy write to Vector Address Register
}
If I modify the ISR like shown below, it is properly working but with a
long delay.
__irq void RTC_ISR(void)
{
k=1;
tmp = RTC->SR; // clear RTC Periodic Interrupt flag
VIC1->VAR=0; // dummy write to Vector Address Register
while (VIC1->VAR !=0);
}
Can any body give me the solution? please, it is very urgent.
Regards,
Neelima
