Why Vectored Interrupt Controller IRQ -1 ?

That's correct. AFAIK those defines are used for internal interrupt controller

thanking you Cris72,

The second function parameter must rather be the actual irq you want to be enabled, not VIC_IRQ.

# include <stdio.h># include "sys/alt_irq.h"# include "system.h"# include "altera_avalon_pio_regs.h"
volatile int edge_capture;
  void handle_load_data_interrupts(void* context, alt_u32 id)
  {
      volatile int* edge_capture_ptr = (volatile int*) context;
      IOWR_ALTERA_AVALON_PIO_IRQ_MASK(LOAD_DATA_BASE, 0x1 );
      *edge_capture_ptr = IORD_ALTERA_AVALON_PIO_EDGE_CAP(LOAD_DATA_BASE);
      IOWR_ALTERA_AVALON_PIO_EDGE_CAP(LOAD_DATA_BASE, 0x1);
      IORD_ALTERA_AVALON_PIO_EDGE_CAP(LOAD_DATA_BASE);
  }
  void init_load_pio()
  {
  void* edge_capture_ptr = (void*) &edge_capture;
  IOWR_ALTERA_AVALON_PIO_IRQ_MASK(LOAD_DATA_BASE, 0x1);
  IOWR_ALTERA_AVALON_PIO_EDGE_CAP(LOAD_DATA_BASE, 0x1);
  alt_ic_isr_register(LOAD_DATA_IRQ_INTERRUPT_CONTROLLER_ID, LOAD_DATA_IRQ, handle_load_data_interrupts, edge_capture_ptr, 0x0);
  }
int main()
{
     int     rc;
    rc = alt_ic_irq_enable(VIC_INTERRUPT_CONTROLLER_ID,VIC_IRQ);
    if(rc<0) printf("\n\tEnhance Interrupt not enabled, Return value = %d",rc);
    else      printf("\n\tEnhnace interrupt       enabled, Return value = %d",rc);
     printf("\n\tInitillize the Enhanced Interrupt..");
     init_load_pio();     
  return 0;
}

Hello Cris, i think you are indicating the Hardware Interrupt, i mean my LOAD_DATA pulse which is coming form outside having priority no. 3.

Exactly. That's what I meant.

Thanking you Cris

Using interrupts in OS environment is usually not recommended because it's easy to mess up everything.

Hello There,

int main()
{
     int rc;
     unsigned long int count =0;
    printf("\n\tInitillize the Enhanced Interrupt..");
   # ifdef LOAD_DATA_BASE
        init_load_data();
   # endif
     rc = alt_ic_irq_enable(VIC_INTERRUPT_CONTROLLER_ID,LOAD_DATA_IRQ);
     if(rc<0)     printf("\n\tEnhance Interrupt NOT enabled, Return value = %d\n",rc);
     else         printf("\n\tEnhnace interrupt ENABLED, Return value = %d\n",rc);
/* //---Should i add these alt_ic_irq_enable for other peripheral also...........??    
    rc = alt_ic_irq_enable(VIC_INTERRUPT_CONTROLLER_ID,JTAG_UART_IRQ);
    rc = alt_ic_irq_enable(VIC_INTERRUPT_CONTROLLER_ID,SYS_CLK_TIMER_IRQ);
*/
     IOWR_ALTERA_AVALON_PIO_DATA(STRT_OUT_BASE,HIGH); //Generate Start Signal
            do
              {
                  if(edge_capture)
                  {
                  IOWR_ALTERA_AVALON_PIO_DATA(TEMP_OUT_BASE,0x1);    //TEMP_OUT not Visible on Oscilloscope
                  edge_capture = 0;                            //Clear Interrupt
                  //printf("\nHIGH");  //Visible on Console
                  }
                  IOWR_ALTERA_AVALON_PIO_DATA(TEMP_OUT_BASE,0x0);
                  //printf("\t\tLOW\n"); //Visible on Console
              }while(1);
     return 0;
}

You set TEMP_OUT to 1 then you immediately deassert it to 0. If you are sure your isr is being serviced, then you simply can't see the pulse on oscilloscope because the signal doesn't have enough time to switch high.