app_error_save_and_stop, where is the error saved?

[kfcube]

I am looking at the APP_ERROR_CHECK and find out it finally goes to the app_error_save_and_stop method. I couldn't understand from the code, that where the error info saved and how I can look in those errors?

Thanks,

[awneil]

Have you looked at the source code?

The documentation says it just enters an infinite loop:

infocenter.nordicsemi.com/.../group__app__error.html

[kfcube]

Got it. It says: Function for saving the parameters and entering an eternal loop, for debug purposes. So, where those parameters saved?

Thanks

[awneil]

Again, 

Have you looked at the source code?

[kfcube]

If you are talking about these codes as following, yes I did, but don't understand. Can u explain? Thanks,

void app_error_save_and_stop(uint32_t id, uint32_t pc, uint32_t info)
{
/* static error variables - in order to prevent removal by optimizers */
static volatile struct
{
uint32_t fault_id;
uint32_t pc;
uint32_t error_info;
assert_info_t * p_assert_info;
error_info_t * p_error_info;
ret_code_t err_code;
uint32_t line_num;
const uint8_t * p_file_name;
} m_error_data = {0};

// The following variable helps Keil keep the call stack visible, in addition, it can be set to
// 0 in the debugger to continue executing code after the error check.
volatile bool loop = true;
UNUSED_VARIABLE(loop);

m_error_data.fault_id = id;
m_error_data.pc = pc;
m_error_data.error_info = info;

switch (id)
{
case NRF_FAULT_ID_SDK_ASSERT:
m_error_data.p_assert_info = (assert_info_t *)info;
m_error_data.line_num = m_error_data.p_assert_info->line_num;
m_error_data.p_file_name = m_error_data.p_assert_info->p_file_name;
break;

case NRF_FAULT_ID_SDK_ERROR:
m_error_data.p_error_info = (error_info_t *)info;
m_error_data.err_code = m_error_data.p_error_info->err_code;
m_error_data.line_num = m_error_data.p_error_info->line_num;
m_error_data.p_file_name = m_error_data.p_error_info->p_file_name;
break;
}

UNUSED_VARIABLE(m_error_data);

// If printing is disrupted, remove the irq calls, or set the loop variable to 0 in the debugger.
__disable_irq();

while(loop);

__enable_irq();
}

[awneil]

So there you can see where the stuff is!

[kfcube]

Thanks for the tip. But still you are answering me. I am still not clear. Can't you just give a direct answer?

[awneil]

Here:

static volatile struct
{
    uint32_t        fault_id;
    uint32_t        pc;
    uint32_t        error_info;
    assert_info_t * p_assert_info;
    error_info_t  * p_error_info;
    ret_code_t      err_code;
    uint32_t        line_num;
    const uint8_t * p_file_name;
} m_error_data = {0};

[kfcube]

How do I access it? just printf m_error_data?

[awneil]

Well, if you're in that place it means your system is in a mess;  so printing may well be "disrupted" - as the comment says.

You could try it to see if it works.

If not, put a breakpoint in that function and examine the data using the debugger.

Failing that, save the data in a "safe" area of RAM that will survive a reboot. Then reboot, and print the info at startup.

How to setup a "safe" area of RAM that will survive a reboot depends on what tools you're using - which you haven't mentioned.

But these are pretty standard debugging techniques - not specific to Nordic - so some general googling should find the answer ...

EDIT

Here's an example for SES (also mentions IAR):

https://devzone.nordicsemi.com/f/nordic-q-a/42331/hi-i-am-using-segger-embedded-stodio-__no_init-not-work