ELF downloaded but switchers don't respond !!!

[Altera_Forum]

hello 

I am working on niosII 13.0 web edition trying to command 2 LEDs using 2 Switchers on Cyclone III board the niosII console shows that the elf is downloaded BUT when i click on Sw nothing happens !! what could be the problem ?!  Downloading 00004000 ( 0%)Downloading 00004F0C (61%)Downloaded 4KB in 0.0s Verifying 00004000 ( 0%)Verifying 00004F0C (61%)Verified OK Starting processor at address 0x00004020

[Altera_Forum]

#include "io.h" 

# include "system.h"  /**  * Gets led_pattern as parameter in order to write to the register.  */ void set_led(unsigned char led_pattern) {  IOWR(LED_BASE, 0, led_pattern); // writes register }  /**  * Main, what else?  * Gets LEDs pattern from switchers.  * Sets LEDs register according to the pattern.  **/ void main() {  unsigned char led_pattern = 0x00;   while (1) { // infinite loop  led_pattern = IORD(SWITCHER_BASE, 0); // gets LEDs  set_led(led_pattern); // sets LEDs  } }