Write Application Data to Flash with pstorage

[Marius R.]

Hi,

i am having trouble to understand and use flash to store data. First of all as far as i understand ble_flash is obsolete and replaced by the pstorage module, correct?

What i want to achieve is, i want to save user settings to flash to be able to set my system to the same state after it has been e.g. reset. Therefore i need to write, erase, read and update existing settings to/in flash.

I read the following documentation part and used it as base of my own code: devzone.nordicsemi.com/.../a00018.html

Do i need to change any addresses in pstorage_platform to match it to my application? I was not sure whether i need to change code in pstorage_platform or not so i didn't changed anything.

The coded i copied from the documentation and the code i added is shown in the file attached.

The pstorage_init is called in my init_app_data_flash_manager function and after the ble_stack_init. Futhermore pstorage_init is called only once.

    // Initialize in main
leds_init();
timers_init();
gpiote_init();
buttons_init();
ble_stack_init();
init_app_data_flash_manager();
scheduler_init();    
gap_params_init();
services_init();
advertising_init();
conn_params_init();
sec_params_init();

My code does the following like descibed in the documentation. I register one block with specific size (in bytes) after pstorage_init. The handle generated while registering is saved and later used to read/write to get a block_handle using pstorage_block_identifier_get. Afterwards this block handle is used to read/write using pstorage_load and pstorage_store.

To test all this I write and read to flash after my device is disconnected (see BLE_GAP_EVT_DISCONNECTED). I also stop adversting to read and write to flash so radio should be inactiv.

            case BLE_GAP_EVT_DISCONNECTED:
        m_conn_handle = BLE_CONN_HANDLE_INVALID;
        
            //advertising_start();
			//test_app_system_settings is empty, test data is generated in save_settings_to_flash

					save_settings_to_flash(&test_app_system_settings);
					read_settings_from_flash(&test_app_system_settings);
        break;

When i debug it the array i read in read_settings_from_flash is empty (just zero).

Can anyone tell me what i am doing wrong and/or help me get it working?

Regards

code.c

Edit: I almost forgot the maybe most importat thing: How do I manage to read and write to the same address every time cause the address i wrote to in the first place is gone after a reset and saving it to flash is not possible cuase this would require a address i dont know after reset as well?

[wins]

For all, who still travel in dark - see answer Nordic employee Stefan Birnir Sverrisson

It also include example (wow! at the end!!! incredible)!

devzone.nordicsemi.com/.../

For clearification:

0) Using documentation only you can erase->save and after that wait (in my case i comment save section, uncomment read section and upload new firmware after a minute) you can (proove it possible) read data.

1) All operations takes time and going not in main thread - you need special loop for it

2) Handler for indicating only. Stop trying implement your routine on it.

handler(pstorage_handle_t  * handle,
                            uint8_t              op_code,
                            uint32_t             result,
                            uint8_t            * p_data,
                            uint32_t             data_len)

switch(op_code)
	    {
		    case PSTORAGE_***_OP_CODE:

3) Short version.

pstorage_handle_t       handle;
pstorage_handle_t	      block_0_handle;
pstorage_handle_t	      block_1_handle;
pstorage_module_param_t param;
uint32_t                retval;
uint8_t                 source_data[16] = {0x31, 0x32, 0x33, 0x34, ...};
uint8_t                 dest_data[16];

//@me init it
retval = pstorage_init();
	if(retval != NRF_SUCCESS)
	{
			nrf_gpio_pin_set(PSTORAGE_ERROR_LED_PIN_NO);
	}

//@me meter of taste - in theory
param.block_size  = 16;                   //Select block size of 16 bytes
param.block_count = 10;                   //Select 10 blocks, total of 160 bytes
param.cb          = example_cb_handler;   //Set the pstorage callback handler

//@me register it
retval = pstorage_register(&param, &handle);
	if (retval != NRF_SUCCESS)
	{
			nrf_gpio_pin_set(PSTORAGE_ERROR_LED_PIN_NO);
	}

//@me WHAT? couple of handles???
//Get block identifiers
pstorage_block_identifier_get(&handle, 0, &block_0_handle);

pstorage_clear(&block_0_handle, 48);                       //Clear 48 bytes

//Store data to blocks. Wait for the last store operation to finish before reading out the data.
//Write to flash, only one block is allowed for each pstorage_store command
pstorage_store(&block_0_handle, source_data, 16, 0);

pstorage_wait_handle = block_1_handle.block_id;            //Specify which pstorage handle to wait for
pstorage_wait_flag = 1;                                    //Set the wait flag. Cleared in the example_cb_handler
pstorage_store(&block_1_handle, source_data, 16, 0);    

//@me need to wait last task in queue
while(pstorage_wait_flag) { power_manage(); }              //Sleep until store operation is finished.
	
//@me now we can check data from our couple of blocks
pstorage_load(dest_data, &block_0_handle, 16, 0);				 //Read from flash, only one block is allowed for each pstorage_load command
pstorage_load(dest_data, &block_1_handle, 16, 0);				 //Read from flash

and do NOT FORGET

static void example_cb_handler(pstorage_handle_t  * handle,	 
uint8_t              op_code,
                           uint32_t             result,
                           uint8_t            * p_data,
                           uint32_t             data_len)
{
	**if(handle->block_id == pstorage_wait_handle) { pstorage_wait_flag = 0; }**
    ...
} 

ALSO NOT FORGET

// Register with the SoftDevice handler module for System events.
err_code = softdevice_sys_evt_handler_set(sys_evt_dispatch);
APP_ERROR_CHECK(err_code);

<and>

   static void sys_evt_dispatch(uint32_t sys_evt)
   {
        pstorage_sys_event_handler(sys_evt);
    }

[kerem]

I am using the code you linked, I get the pstorage assert led on indicating there is a problem but can't really debug it. I am using nrf51-dk with SDK 6.1.0, am I missing something? How do you debug pstorage?