Storing values using Flash-manager

[Gerry]

Hi Team

I would like to store a simple integer value in flash and read it back after a power cycle. I already studied the library Flash-manager of the nRF5 SDK for Mesh v1.0.1. Since I found no example code this seems quite hard to do. Can you give us some example lines of code to write and read simple values to/from flash?

kind regards

Gerry

 

[FormerMember]

In the regular SDK there is an example showing how to use the flash data storage module (FDS), I would recommend you to take a look at that. The example can be found in the following folder in the SDK: ..\nRF5_SDK_14.2.0_17b948a\examples\peripheral

[Gerry]

Hi Kristin

Thanks for your answer. I already tried to merge FDS and FStorage from the regular SDK with the Mesh SDK 1.0.0. I gave up after a day. Regarding the Infocenter, Flash manager seems to be the way to do this, but there is no samplecode for this.Do you have a sample how this should be done using flash manager?

Kind regards

Gerry

[FormerMember]

Yes, after a closer look at it, I see that  the "flash manager" mesh library is the best to use. 
Unfortunately, I don't have any sample code. 

Mesh will use the 4 pages right  before the en of the flash page or right before the bootloader.  Your application should use another area.

[Gerry]

Hi Kristin

I think it would be good to have an example for that, since it makes not much sense to write a mesh application without beeng able to persistantly store values or settings and its not an easy task to do so with the information given in the infocenter. So I made some example code to store and read back from flash. Maybe you can fix it and then other developers can use it also.

Kind regards Gerry

// Init Flash
flash_manager_init ();
#define FLASH_HANDLE_METADATA 0x0002
const fm_entry_t * p_metadata_entry = flash_manager_entry_get(&m_flash_manager, FLASH_HANDLE_METADATA);
if (p_metadata_entry == NULL)
{
flash_manager_config_t manager_config;
manager_config.write_complete_cb = NULL; //flash_write_complete;
manager_config.invalidate_complete_cb = NULL; //flash_invalidate_complete;
manager_config.remove_complete_cb = NULL; //flash_remove_complete;
manager_config.min_available_space = WORD_SIZE;
manager_config.p_area = (const flash_manager_page_t *) (((const uint8_t *) dsm_flash_area_get()) - (ACCESS_FLASH_PAGE_COUNT * PAGE_SIZE));
manager_config.page_count = ACCESS_FLASH_PAGE_COUNT;
uint32_t status = flash_manager_add(&m_flash_manager, &manager_config);
if (NRF_SUCCESS != status) {
__LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "Flash error: no memory\n",status);
}
}

//Write to Flash
#define FLASH_GROUP_ELEMENT 0x1500
uint16_t element_index = 1;
fm_entry_t * p_entry = flash_manager_entry_alloc(&m_flash_manager, FLASH_GROUP_ELEMENT | element_index, sizeof(uint16_t));
if (p_entry == NULL)
{
return NRF_ERROR_BUSY;
}
else
{
uint16_t fstore = 7;
uint32_t data_[] = {1,2};
uint16_t * p_element_location = (uint16_t *) p_entry->data;
*p_element_location = 7;
flash_manager_entry_commit(p_entry);
__LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "write:%u\n",p_entry);
}

waitevent();

//Read from Flash
const fm_entry_t * fread = flash_manager_entry_get(&m_flash_manager, FLASH_GROUP_ELEMENT);
__LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "read:%u\n",*fread);

[FormerMember]

Yes, I agree that there should be a mesh example showing how to store persistent data. 

Thanks for sharing your code! I will add it to an example so that it easily can be tested.