Easy nios design with buttons

Hello,

I've been doing some other stuff and I am now back to my button design.

I checked my pin assignments (they are fine) and my base addresses for PIOS in SOPC and the ones in "system.h" matches.

I tried the easy program below and when I press the button, nothing happens. It seems that there is still another connection problem but I don't know which one.

int alt_main (void)

{

alt_u8 button = 0x2;

while(1){

button = IORD_ALTERA_AVALON_PIO_DATA(PIO_0_BASE);

if (button==0x01)

printf("button 1");

}

return 0;

}

Thanks for your patience,

Myriam