Problem wid nios ii APIs

Hello all,

I'm using Quartus v13.1 on my DE2-70 board with the cyclone II fpga. I want to enable interrupts using toggle switches. It worked when using the Altera ehanced interrrupt API (#include"altera_avalon_pio_regs.h"), However I tried using the nios 2 API (because we have some tutorials using it ) and It does not seem to work. For eg:

I tried using the functions such as : __builtin_wrctl(3, 2) and __builtin_wrctl(0, 1) to write into the ienable and status register respectively. When i read the ipending register (ipending = __builtin_rdctl(4)) it shows 0 . I also tried replacing it with the nios 2 macros without much success. Here is the code i used:

#include <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include "system.h"

#include "nios2.h"

volatile uint32_t *LED = (volatile uint32_t *) LEDS_BASE; /* Green leds base address*/

volatile uint32_t * slides = (volatile uint32_t *) 0x41000; /* slider switches base address*/

void toggle_isr()

{

int press;

press = *(slides+3); /* read the switch edge capture register*/

//*(slides+3) = 0; /* clear the interrupt */

printf("Hello from Nios 3! \n");

while(1)

{

printf("Hello from Nios I4! \n");

if ((press & (1 << 1)) != 0) /* SW[1] */

{

printf("Hello from Nios II! %d \n", *LED);

if(*LED == 0xFF)

*LED = 0;

(*LED)++;

usleep(100000);

}

}

}

void interrupt_handler(void)

{

int ipending, status;

printf("Hi! \n");

NIOS2_READ_STATUS(status);

printf("HhgfghfjhgfghfI! %d \n", status);

NIOS2_READ_IPENDING(ipending);

printf("Hello from Nios II! %d \n", ipending);

//if (((ipending & (1 << 1))) != 0 ) // toggle switches is interrupt level 1

if (ipending != 0) // checking for enabled interrupts in general*/

{

printf("Hello from Nios 2! %d \n", ipending);

toggle_isr();

}

// else, ignore the interrupt

return;

}

int main()

{

*(slides+2) = 0x3;

NIOS2_WRITE_IENABLE(0x2);

NIOS2_WRITE_STATUS(1); /* enable Nios II interrupts*/

interrupt_handler();

return 0;

}

Is there a reason why it is not working (errors in the code above, obsolete functions …)?