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Altera_Forum's avatar
Altera_Forum
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15 years ago

Problem in registering ISR (C++)

HI.

I'm doing my thesis on a DE2 board. I'm using a NIOS II processor. I've been writing all my source code in C. That way, it worked perfectly.

I had to ****ch to C++ for a few reasons (which I'm not gonna explain here). The thing is: I have some problems to register an ISR.

This is the "old" code (which works in C): 

void simpler_isr()
{
    for(j=0; j<3; j++)
    {
        store_array = IORD(FULL_CLASIFIER_0_BASE, 0x00);
    }
    i++;
    flag++;
}

and this is the part where I register the isr: 

alt_ic_isr_register(FULL_CLASIFIER_0_IRQ_INTERRUPT_CONTROLLER_ID,
                        FULL_CLASIFIER_0_IRQ,
                        simpler_isr,
                        NULL,
                        0x0);

When I tried to compile in C++, I got this error mesage:

initializing argument 3 of `int alt_ic_isr_register(alt_u32, alt_u32, void (*)(void*), void*, void*)'

invalid conversion from `void (*)()' to `void (*)(void*)'

So, I changed the ISR this way: 

void simpler_isr(void*)
{
    for(j=0; j<3; j++)
    {
        store_array = IORD(FULL_CLASIFIER_0_BASE, 0x00);
    }
    i++;
    flag++;
}

Now, I get this message:

Undefined reference to "main"

I don't know what I'm missing.

THANKS.

9 Replies

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

    I respond myself:

    I did a "make clean" and I solve the last problem. Now, I have another one.

    It seems that the ISR registration never occurs. I put a cout next to alt_ic_isr_register, and it never appears on stdout (screen).

    Any suggestions??

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

    Hi,

    1. You can "debug" ;-)

    2. stdout = screen ? sure ? Look at if it is not an UART instead of JTAG UART (or the opposite).

    3. Maybe you use light drivers for printf or cout. I don't know the new (since 9.2) NIOS Software Built Tool.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Hello.

    As I said, the project was written in C, and it worked.

    The only thing I did was adding C++ stuff and "migrate" to a C++ project.

    Greetings.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Are you sure that any of your code is now running?

    Or it might all be dying horribly before the text is actually written to the uart.

    Even in C++ I'd use use printf(), 'cout' adds an extra level complexity (and unusability) that might be masking things. If you suspect a lockup you need a synchronous write - not one that is buffered and/or requires interrupts to complete.

    You might also need to mark the ISR as 'extern "C"' - but that would (probably) only affect the symbol name, not the address passed.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Hello.

    I've just tried the simpler C++ program (Hello World) and it didn't work. I tried with cout, I tried with printf. The project compiles, but the program does nothing.

    Once I compile the project, these are the commands I'm using:

    nios2-download -g holamundo.elf

    Using cable "USB-Blaster [USB 4-1.3]", device 1, instance 0x00

    Pausing target processor: OK

    Initializing CPU cache (if present)

    OK

    Downloaded 53KB in 1.0s (53.0KB/s)

    Verified OK

    Starting processor at address 0x008001C4

    nios2-terminal

    nios2-terminal: connected to hardware target using JTAG UART on cable

    nios2-terminal: "USB-Blaster [USB 4-1.3]", device 1, instance 0

    nios2-terminal: (Use the IDE stop button or Ctrl-C to terminate)

    .... and nothing happens.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Ok,you meant to say code is downloaded ,you put printf after ISR declaration and nothing happens though all is perfectly fine as JTAG UART and all,right?

    Do one thing,just put printf (or cout) immediately after main(),and see it displays on console when running.what happenes..!! It should display

    If still not then delete whole file from the project (save backup somehere),clean and add it again.And manually RESET ur hardware or download SOF again and then run the code.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Hi Supal.

    I had done everything you said. Nothing happened.

    I'm starting thinking that is a problem related to the PC I'm using. I'm gonna try to do it in other PC.

    Thanks!!!
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Check if your output is really your UART.. double check the adresses and everything else.

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

    I re-assigned the addresses via SOPC

    I check by BSP editor, and:

    stderr -> jtag_uart

    stdin -> jtag_uart

    stdout -> jtag_uart

    I regenerated the BSP

    I compiled the project

    I downloaded (nios2-dowload -g project.elf). I ran nios2-terminal... and nothing happened... I don't really know what to do.