Using the SDRAM Controller with Qsys

[Altera_Forum]

I am trying to use Eclipse to program an application using the lcd. My qsys system uses an sdram controller. I receive a single error in the alt_main.c which was generated in the bsp. 

 The error states undefined reference to main. It occurs in the return line of the code   extern int main (int, char **, char **);    void alt_main (void)     {    #ifndef ALT_NO_EXIT     int result;         # endif           /* ALT LOG - please see HAL/sys/alt_log_printf.h for details */    ALT_LOG_PRINT_BOOT("[alt_main.c] Entering alt_main, calling alt_irq_init.\r\n");    /* Initialize the interrupt controller. */       alt_irq_init (NULL);       /* Initialize the operating system */    ALT_LOG_PRINT_BOOT("[alt_main.c] Done alt_irq_init, calling alt_os_init.\r\n");       ALT_OS_INIT();       /*         * Initialize the semaphore used to control access to the file descriptor     * list.     */          ALT_LOG_PRINT_BOOT("[alt_main.c] Done OS init, calling alt_sem_create.\r\n");       ALT_SEM_CREATE (&alt_fd_list_lock, 1);       /* Initialize the device drivers/software components. */    ALT_LOG_PRINT_BOOT("[alt_main.c] Calling alt_sys_init.\r\n");       alt_sys_init();     ALT_LOG_PRINT_BOOT("[alt_main.c] Done alt_sys_init.\r\n");         #if !defined(ALT_USE_DIRECT_DRIVERS) && (defined(ALT_STDIN_PRESENT) || defined(ALT_STDOUT_PRESENT) || defined(ALT_STDERR_PRESENT))         /*         * Redirect stdio to the apropriate devices now that the devices have     * been initialized. This is only done if the user has requested these     * devices be present (not equal to /dev/null) and if direct drivers     * aren't being used.     */          ALT_LOG_PRINT_BOOT("[alt_main.c] Redirecting IO.\r\n");       alt_io_redirect(ALT_STDOUT, ALT_STDIN, ALT_STDERR);    #endif           #ifndef ALT_NO_C_PLUS_PLUS    /*          * Call the C++ constructors      */          ALT_LOG_PRINT_BOOT("[alt_main.c] Calling C++ constructors.\r\n");       _do_ctors ();    #endif/* ALT_NO_C_PLUS_PLUS */         #if !defined(ALT_NO_C_PLUS_PLUS) && !defined(ALT_NO_CLEAN_EXIT) && !defined(ALT_NO_EXIT)    /*         * Set the C++ destructors to be called at system shutdown. This is only done     * if a clean exit has been requested (i.e. the exit() function has not been     * redefined as _exit()). This is in the interest of reducing code footprint,     * in that the atexit() overhead is removed when it's not needed.     */          ALT_LOG_PRINT_BOOT("[alt_main.c] Calling atexit.\r\n");       atexit (_do_dtors);    #endif           /*         * Finally, call main(). The return code is then passed to a subsequent     * call to exit() unless the application is never supposed to exit.     */          ALT_LOG_PRINT_BOOT("[alt_main.c] Calling main.\r\n");         #ifdef ALT_NO_EXIT       main (alt_argc, alt_argv, alt_envp);    #else         result = main (alt_argc, alt_argv, alt_envp);     close(STDOUT_FILENO);     exit (result);    #endif            ALT_LOG_PRINT_BOOT("[alt_main.c] After main - we should not be here?.\r\n");      }   This error does not occur when using on-chip memory, however that won't be sufficient for the project according to eclipse. How should I approach fixing the error?

[Altera_Forum]

Hi, 

 It seems that the problem isn't the SDRAM controller, Rather, make sure that the c file containing your "main" is correctly added to your project.  Check the following line in the Makefile of your project : # Paths to C, C++, and assembly source files. C_SRCS := ...  regards,

[Altera_Forum]

Hello all, 

This code has been tested with the BeMicroMax and it will be help you to test your SDRAM memory : We assume that you are set your memory controller with QSYS : In my case the memory controller is mapped at the address : (0x800000)# define SDRAM_BASE (0x800000)# define SDRAM_BASE_MUX (SDRAM_BASE + 0x2000) /** Offset for the exception */  /** Variables */ uint32_t u32AddrSram = 0; uint16_t u16Value = 0; uint16_t u16ReadSramValue = 0;    /** example for write and read only one byte at the time in the sram */  for( u32AddrSram = 0; u32AddrSram< 100 ; u32addrsram += 0x08)  {  /** Write Data */  alt_printf("\n*** SDRAM WRITE[%x] VALUE = %x \n\r ", (SDRAM_BASE_MUX + u32AddrSram) , (uint8_t)(u16Value));  iowr_8direct(SDRAM_BASE_MUX, (uint16_t)u32AddrSram, (uint8_t)u16Value);   /** Read Data */  u16ReadSramValue = iord_8direct(SDRAM_BASE_MUX, u32AddrSram);  alt_printf("\n*** SDRAM READ[%x] VALUE = %x \n\r ", (SDRAM_BASE_MUX + u32AddrSram), u16ReadSramValue);  /** Change the value */  u16Value++;  }   /** example for write and read only 2bytes at the time in the sram */  u16Value = 0xA000;  for( u32AddrSram = 0; u32AddrSram< 100 ; u32addrsram += 0x10)  {  /** Write Data */  alt_printf("\n*** SDRAM WRITE[%x] VALUE = %x \n\r ", (SDRAM_BASE_MUX + u32AddrSram) , (uint16_t)(u16Value));  iowr_16direct(SDRAM_BASE_MUX, (uint16_t)u32AddrSram, (uint16_t)u16Value);   /** Read Data */  u16ReadSramValue = iord_16direct(SDRAM_BASE_MUX, u32AddrSram);  alt_printf("\n*** SDRAM READ[%x] VALUE = %x \n\r ", (SDRAM_BASE_MUX + u32AddrSram), u16ReadSramValue);  /** Change the value */  u16Value++;  }   /*** Result for Byte */ *** SDRAM WRITE[802000] VALUE = 0  *** SDRAM READ[802000] VALUE = 0     *** SDRAM WRITE[802008] VALUE = 1  *** SDRAM READ[802008] VALUE = 1     *** SDRAM WRITE[802010] VALUE = 2  *** SDRAM READ[802010] VALUE = 2     *** SDRAM WRITE[802018] VALUE = 3  *** SDRAM READ[802018] VALUE = 3     *** SDRAM WRITE[802020] VALUE = 4  *** SDRAM READ[802020] VALUE = 4     *** SDRAM WRITE[802028] VALUE = 5  *** SDRAM READ[802028] VALUE = 5     *** SDRAM WRITE[802030] VALUE = 6  *** SDRAM READ[802030] VALUE = 6     *** SDRAM WRITE[802038] VALUE = 7  *** SDRAM READ[802038] VALUE = 7     *** SDRAM WRITE[802040] VALUE = 8  *** SDRAM READ[802040] VALUE = 8     *** SDRAM WRITE[802048] VALUE = 9  *** SDRAM READ[802048] VALUE = 9     *** SDRAM WRITE[802050] VALUE = a  *** SDRAM READ[802050] VALUE = a     *** SDRAM WRITE[802058] VALUE = b  *** SDRAM READ[802058] VALUE = b     *** SDRAM WRITE[802060] VALUE = c  *** SDRAM READ[802060] VALUE = c    /** result for 2bytes read */ *** SDRAM WRITE[802000] VALUE = a000  *** SDRAM READ[802000] VALUE = a000     *** SDRAM WRITE[802010] VALUE = a001  *** SDRAM READ[802010] VALUE = a001     *** SDRAM WRITE[802020] VALUE = a002  *** SDRAM READ[802020] VALUE = a002     *** SDRAM WRITE[802030] VALUE = a003  *** SDRAM READ[802030] VALUE = a003     *** SDRAM WRITE[802040] VALUE = a004  *** SDRAM READ[802040] VALUE = a004     *** SDRAM WRITE[802050] VALUE = a005  *** SDRAM READ[802050] VALUE = a005     *** SDRAM WRITE[802060] VALUE = a006  *** SDRAM READ[802060] VALUE = a006