Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Easy nios design with buttons

Hello,

I am a newbie with Quartus II and Nios II and I have been trying to do an easy nios design in order to light on a led when pressing a button. I am working on the Altera Cyclone III EP3C25F324 board. I think the problem comes from my code in nios II that I put below. I don't really know when to write "IOWR_ALTERA_AVALON_PIO_DATA(...);" maybe the problem comes from here. Plus, when I try to write some "printf", there is an error :

collect2: ld returned 1 exit status

make: *** [button_led.elf] Error 1

Here is my program :

#include "system.h"# include "altera_avalon_pio_regs.h"# include "alt_types.h"# include "stdio.h"# include "stdlib.h"

int alt_main (void)

{

alt_u8 led = 0x2;

alt_u8 button = 0x2;

IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE, led);

IOWR_ALTERA_AVALON_PIO_DATA(BUTTON_PIO_BASE, button);

while (1)

{

switch (button) {

case 0x1 :

led=0x1;

break;

case 0x2 :

led=0x2;

break;

case 0x4 :

led=0x4;

break;

case 0x8 :

led=0x8;

break;

}

}

Do someone can help me?

Thank you very much,

Myriam

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    try this:

    # include "system.h"# include "altera_avalon_pio_regs.h"# include "alt_types.h"# include "stdio.h"# include "stdlib.h"

    int alt_main (void){

    alt_u8 button = 0x2;

    while(1){

    button = IORD_ALTERA_AVALON_PIO_DATA(BUTTON_PIO_BASE);

    IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE, button);

    }

    }
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    It lights on the 4 leds without any change when I press a button.

    Maybe it comes from my quartus II design ?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    I would double check the pin connections of the buttons . A good tip is to use signal tap to see if anything happens on those pins.

    //Bango
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    I am trying your idea but it is the first time I am unsing the tap signal interface and I am not succeeding. I read the literature on Altera but I still don't understand my mistakes. First, a word about my design. I added to the CIII_NiosII_Small design provided by Altera a BUTTON[3..0] signal as another entry. On the SignalTap II Embedded Logic Analyzer, I added the four signal (corresponding to each button), the clock and entered the hardware setup (USB).

    Now I have errors from the Analyzer :

    ISED_PROGRAM_DEVICE CAUSE: You attempted to run the SignalTap II Logic Analyzer, but the current design does not match the design programmed in the device. ACTION: Program the device with the current design, and re-attempt to run the run the SignalTap II Logic Analyzer.

    And from Quartus :

    Error: Current license file does not support incremental compilation

    Can you help me ?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    1. Check your pin assignments.

    2. Verify that your base addresses for PIOS in SOPC are same that ones in "system.h".
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    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
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    Hello,

    Maybe it's the problem of alt_main(), unlike main(), some driver initialization should be added manually.

    # include "sys/alt_sys_init.h"

    in alt_main():

    alt_sys_init();

    alt_io_redirect (ALT_STDOUT, ALT_STDIN, ALT_STDERR);

    I haven't checked myself it yet. but you could try using main() instead if you have enough RAM

    Yue