What should I start in order to use the maximum memory space in fstorage?

RE: What should I start in order to use the maximum memory space in fstorage?

Katie Newell — Fri, 04 Dec 2020 13:37:55 GMT

Hi Kristin,

Thanks for sharing this, it is very clear and helpful.

I am struggling to write uint8 or uint16 into the Flash using your fds_write function. I am getting this FDS error FDS_ERR_UNALIGNED_ADDR.

Could you help me understand why please?

Many thanks

RE: What should I start in order to use the maximum memory space in fstorage?

purgoufr — Tue, 20 Mar 2018 05:49:48 GMT

After Kristin's help, I finally get the solution.

I do not know exactly why, If you want to record a sequence directly, it gives an error. So I have defined external an array( m_deadbeef[10] ) in the fds_write function. Then I copied the array that I want to save into m_deadbeef. And the problem is solved.

static ret_code_t kls_fds_write(uint32_t write_file_id, uint32_t write_record_key , uint8_t write_data[])
{		
		static uint8_t m_deadbeef[10] = {0};
		
		memcpy(m_deadbeef, write_data, sizeof(m_deadbeef));
		
		fds_record_t        record;
		fds_record_desc_t   record_desc;
	
		// Set up record.
		record.file_id              = write_file_id;
		record.key              		= write_record_key;
		record.data.p_data       		= &m_deadbeef;
		record.data.length_words   	= sizeof(m_deadbeef)/sizeof(uint8_t);
				
		ret_code_t ret = fds_record_write(&record_desc, &record);
		if (ret != FDS_SUCCESS)
		{
				return ret;
		}
		 NRF_LOG_INFO("Writing Record ID = %d \r\n",record_desc.record_id);
		return NRF_SUCCESS;
	
}
	
static ret_code_t kls_fds_read(uint32_t read_file_id, uint32_t relevant_record_key , uint8_t read_data[])
{	
		fds_flash_record_t  flash_record;
		fds_record_desc_t   record_desc;
		fds_find_token_t    ftok ={0};//Important, make sure you zero init the ftok token
		uint8_t *data;
		uint32_t err_code;
		
		NRF_LOG_INFO("Start searching... \r\n");
		// Loop until all records with the given key and file ID have been found.
		while (fds_record_find(read_file_id, relevant_record_key, &record_desc, &ftok) == FDS_SUCCESS)
		{
				err_code = fds_record_open(&record_desc, &flash_record);
				if ( err_code != FDS_SUCCESS)
				{
					return err_code;		
				}
				
				NRF_LOG_INFO("Found Record ID = %d\r\n",record_desc.record_id);

				data = (uint8_t *) flash_record.p_data;
				for (uint8_t i=0;i<flash_record.p_header->length_words;i++)
				{
					read_data[i] = data[i];
				}
			
		
				NRF_LOG_HEXDUMP_INFO(read_data, sizeof(read_data));
				// Access the record through the flash_record structure.
				// Close the record when done.
				err_code = fds_record_close(&record_desc);
				if (err_code != FDS_SUCCESS)
				{
					return err_code;	
				}
		}
		return NRF_SUCCESS;	
}

RE: What should I start in order to use the maximum memory space in fstorage?

purgoufr — Mon, 19 Mar 2018 10:18:57 GMT

Should it be Const? Because I am trying to save the data from nus_data. The variable type here is uint8_t * p_data (Not const) as you know.

Also I tried this one;

static uint8_t const m_deadbeef[10] = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x10};

and Writing has not occurred.

static uint8_t const m_deadbeef[8] = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08}; is working

static uint8_t const m_deadbeef[10] = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x10}; is not working

I have not changed anything(except m_deadbeef size) . Pretty odd! .

RE: What should I start in order to use the maximum memory space in fstorage?

FormerMember — Mon, 19 Mar 2018 09:11:31 GMT

The example works fine with longer arrays as well, the variable holding the data has to be declared the following way:

static uint8_t const m_deadbeef[xx ] = ...

RE: What should I start in order to use the maximum memory space in fstorage?

purgoufr — Sat, 17 Mar 2018 10:48:34 GMT

in fds_test_write function, it write 4 bytes not 10;
"static uint8_t const m_deadbeef[4] = {0x1,0x2,0x3,0x4};"

The write function does not work when there are 8 or more bytes. For example I modified like this;

static uint8_t m_deadbeef[8] = {0x41,0x30,0x31,0x31,0x30,0x30,0x30,0x34}; and it worked.

But I tried this;

static uint8_t m_deadbeef[10] = {0x41,0x30,0x31,0x31,0x30,0x30,0x30,0x34,0x30,0x24}; and it did not work.

It does not work if it is bigger than eight.

RE: What should I start in order to use the maximum memory space in fstorage?

FormerMember — Fri, 16 Mar 2018 12:38:37 GMT

The function fds_test_write() shows how to do that.

RE: What should I start in order to use the maximum memory space in fstorage?

purgoufr — Thu, 15 Mar 2018 12:41:14 GMT

Kristin, I learned a lot from your answer. If I can read and write a 10 byte uint8_t data(such as below), I will reach the purpose.

static uint8_t m_deadbeef[10] = {0x41,0x30,0x31,0x31,0x30,0x30,0x30,0x34,0x30,0x24};

Could you tell me how to write this uint8_t m_deadbeef[10]?

RE: What should I start in order to use the maximum memory space in fstorage?

FormerMember — Thu, 15 Mar 2018 10:08:39 GMT

Okay, I see. So what you really want to do is to write a an array to flash and then retrieve it again? If so, you can do that the following way:

static ret_code_t fds_read(void)
{

		fds_flash_record_t  flash_record;
		fds_record_desc_t   record_desc;
		fds_find_token_t    ftok ={0};//Important, make sure you zero init the ftok token
		uint8_t *data;
		uint32_t err_code;
		
		NRF_LOG_INFO("Start searching... \r\n");
		// Loop until all records with the given key and file ID have been found.
		while (fds_record_find(FILE_ID_FDS_TEST, REC_KEY_FDS_TEST, &record_desc, &ftok) == FDS_SUCCESS)
		{
				err_code = fds_record_open(&record_desc, &flash_record);
				if ( err_code != FDS_SUCCESS)
				{
					return err_code;		
				}
				
				NRF_LOG_INFO("Found Record ID = %d\r\n",record_desc.record_id);
				NRF_LOG_INFO("Data = ");
				data = (uint8_t *) flash_record.p_data;
				for (uint8_t i=0;i<flash_record.p_header->length_words;i++)
				{
					NRF_LOG_INFO("0x%8x ",data[i]);
				}
				NRF_LOG_INFO("\r\n");
				// Access the record through the flash_record structure.
				// Close the record when done.
				err_code = fds_record_close(&record_desc);
				if (err_code != FDS_SUCCESS)
				{
					return err_code;	
				}
		}
		return NRF_SUCCESS;
		
}

To easily test it, you can replace main.c in ble_app_hrs in SDK 14.2 by this file: devzone.nordicsemi.com/.../main.c

RE: What should I start in order to use the maximum memory space in fstorage?

purgoufr — Thu, 15 Mar 2018 09:06:38 GMT

Thanks for your answer, Kristin. Unfortunately,I could not use FDS. I tried so hard to use it, but I failed. If you want to look my question that is related to FDS, you can find in this LINK .

RE: What should I start in order to use the maximum memory space in fstorage?

FormerMember — Thu, 15 Mar 2018 08:56:47 GMT

I would think that the address 0x3e000 is chosen arbitrary. If you want to store data to flash, I would recommend you to use the FDS module (Flash Data Storage). FDS provides an easy-to-use interface for storing and handling stored data. FDS uses fstorage.

FDS stores data in the last flash pages available.