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Honored ContributorBuild Error using template: /HAL/src/alt_main.c:154: undefined reference to `main'
Hi,
I'm attempting to use the Nios processor for the first time since i've upgraded to Quartus version 12.1 on a Windows 7 machine. The Nios that comes with this version of Quartus is..Version: Indigo Service Release 2. Build id: 20120216-1857 The error i get is:
**** Build of configuration Nios II for project Hello_Led_12_04_13 ****
......
..... (Plenty of build code)
.....
....
Info: Linking Hello_Led_12_04_13.elf
nios2-elf-g++ -T'../Hello_Led_12_04_13_bsp//linker.x' -msys-crt0='../Hello_Led_12_04_13_bsp//obj/HAL/src/crt0.o' -msys-lib=hal_bsp -L../Hello_Led_12_04_13_bsp/ -Wl,-Map=Hello_Led_12_04_13.map -O0 -g -Wall -EL -mno-hw-div -mhw-mul -mno-hw-mulx -o Hello_Led_12_04_13.elf -lm
../Hello_Led_12_04_13_bsp/\libhal_bsp.a(alt_main.o): In function `alt_main':
C:\altera\12.1\WorkingArea\BiggerNios\software\Hello_Led_12_04_13_bsp/HAL/src/alt_main.c:154: undefined reference to `main'
collect2: ld returned 1 exit status
make: *** Error 1
**** Build Finished ****
/************************************************************************** * Copyright (c) 2004 Altera Corporation, San Jose, California, USA. *
* All rights reserved. All use of this software and documentation is *
* subject to the License Agreement located at the end of this file below.*
*************************************************************************/
/******************************************************************************
* DANGER ** WARNING ** Please read before proceeding! ** WARNING ** DANGER *
******************************************************************************
*
* This program is an example of a "free-standing" C application. If you
* modify this example and try to call C library functions such as printf, they
* will NOT work unless you explicitly initialize the system, such as in the
* hello_alt_main software template. Please see below for details.
*
* Description
* *************
* A very minimal program that simply shifts an LED back and forth.
*
* Requirements
* **************
* According to the ANSI C standard, freestanding programs "own" the hardware,
* and cannot rely on system-services or device-drivers being initialized prior
* to program-start. A freestanding program is responsible for initializing all
* hardware devices, device-drivers, and system-services. Many embedded
* programs are, by nature, freestanding. The author relinquishes any illusion
* of running their program on a workstation.
*
* This example is a freestanding program because it's entry point is the
* function:
*
* void alt_main (void)
*
* As opposed to "main()" as a "hosted" application would (see the
* "hello_world" example).
*
* Upon entry to alt_main():
* - The CPU's caches (if any) have been initialized.
* - The stack-pointer has been set.
* - That's all. The rest is up to you.
*
* If you modify this example and try to call C library functions such as
* printf, they will NOT work unless you explicitly initialize the system.
* If you wish to use C library calls, it is strongly suggested you start
* with the hosted hello_world template which uses main() as it's entry
* point.
*
* On the other hand, if you want to write a program that gets-in even
* earlier, you will need to provide your own assembly-language machine-setup
* code by defining the symbol "_start". Any definition of _start in your
* directory will override the library definition. You can find source code
* for the Nios II library _start here:
*
* <NiosII-Kit-Install-Dir>/components/altera_nios2/HAL/src/crt0.S
*
* This software example requires a system with a PIO peripheral named
* "led_pio". The software example will run on the following hardware
* examples:
*
* Nios Development Board, Stratix II Edition:
* - Standard
* - Small
* - Full Featured
*
* DSP Development Board, Stratix II Edition:
* - Standard
* - Small
* - Full Featured
*
* Nios Development Board, Stratix Edition:
* - Standard
* - Small
* - Full Featured
*
* Nios Development Board, Stratix Professional Edition:
* - Standard
* - Small
* - Full Featured
*
* Nios Development Board, Cyclone Edition:
* - Standard
* - Small
* - Low Cost
* - Full Featured
*
* Peripherals Exercised by SW
* *****************************
* The hello_led.c program simply shifts an 8-bit variable back and forth,
* writing the variable's value to the system's LED PIO peripheral on every
* iteration.
*
* Software Files
* ****************
* hello_led.c - Main C file that contains the simple led manipulation routine.
*
*/
# include "system.h"# include "altera_avalon_pio_regs.h"# include "alt_types.h"
/*
* This is a freestanding application, so we want to use alt_main
* as the entry point. However, if the debugger is run on this
* application, it will try to set a breakpoint at main, which
* the application does not contain. The below line creates an
* alias so the debugger is able to set a breakpoint at main,
* yet the application retains alt_main as it's entry point.
*/
int main (void) __attribute__ ((weak, alias ("alt_main")));
/*
* Use alt_main as entry point for this free-standing application
*/
int alt_main (void)
{
alt_u8 led = 0x2;
alt_u8 dir = 0;
volatile int i;
/*
* Infinitely shift a variable with one bit set back and forth, and write
* it to the LED PIO. Software loop provides delay element.
*/
while (1)
{
if (led & 0x81)
{
dir = (dir ^ 0x1);
}
if (dir)
{
led = led >> 1;
}
else
{
led = led << 1;
}
IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE, led);
/*
* The delay element in this design has been written as a while loop
* to avoid confusing the software debugger. A tight, one line software
* delay loop such as:
* for(i=0; i<200000; i++);
* can cause problems when it is stepped through using a software debugger.
* The while loop below produces the same behavior as the for loop shown
* above, but without causing potential debugger problems.
*/
i = 0;
while (i<200000)
i++;
}
return 0;
}
/******************************************************************************
* *
* License Agreement *
* *
* Copyright (c) 2004 Altera Corporation, San Jose, California, USA. *
* All rights reserved. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the "Software"), *
* to deal in the Software without restriction, including without limitation *
* the rights to use, copy, modify, merge, publish, distribute, sublicense, *
* and/or sell copies of the Software, and to permit persons to whom the *
* Software is furnished to do so, subject to the following conditions: *
* *
* The above copyright notice and this permission notice shall be included in *
* all copies or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR *
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE *
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER *
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *
* DEALINGS IN THE SOFTWARE. *
* *
* This agreement shall be governed in all respects by the laws of the State *
* of California and by the laws of the United States of America. *
* Altera does not recommend, suggest or require that this reference design *
* file be used in conjunction or combination with any other product. *
******************************************************************************/
