How to use nRF9160's internal flash to store data

[Liza]

Hi,

I use the nRF9160dk and I want to use nRF9160's internal flash which has 1MB flash to store a few data. But I cannot find any guideline about using nRF9160's internal flash.

So how to use this 1MB flash to store data?

board: nrf9160dk
SDK: v2.5.0

Thanks,

Liza

[Jared]

Hi,

Can you look at this blog post? It lists some storing alternatives available in Zephyr,

regards

Jared

[Liza]

Hi Jared,

I study the NVS sample. I want to ask how to read the stored data instead of the Number of bytes read?

Thanks,

Liza

[Jared]

Hi Liza,

As in the sample you would use the nvs_read() function to read the store data, after you have written it to NVS. The function takes in the ID and the data buffer the buffer where the data should be temporary stored in. Do you have any question related to this function?

regards

Jared 

[Liza]

Hi Jared,

I write int data = 1000 to NVS, and then read from NVS reading = 1000. But after resetting the device, the reading becomes 232. I don't know what's wrong. 

Best regards,

Liza

[Jared]

Hi Liza,

Could you share your code?

regards
Jared 

[Liza]

Hi Jared,

This is the source code:

Fullscreen storage.txt Download

int main(void)
{
        NVSInit();

        return 0;
}



void NVSInit(){
	printk("\nNVS init started...\n");

	/* define the nvs file system by settings with:
	 *	sector_size equal to the pagesize,
	 *	3 sectors
	 *	starting at NVS_PARTITION_OFFSET
	 */
	fs.flash_device = NVS_PARTITION_DEVICE;
	if (!device_is_ready(fs.flash_device)) {
		printk("\n--ERROR: Flash device %s is not ready--\n", fs.flash_device->name);
		exit(1);
	}
	fs.offset = NVS_PARTITION_OFFSET;
	rc = flash_get_page_info_by_offs(fs.flash_device, fs.offset, &info);
	if (rc) {
		printk("\n--REEOR: Unable to get page info--\n");
		exit(1);
	}
	fs.sector_size = info.size;
	fs.sector_count = 3U;    
	printk("info.size = %d\n",fs.sector_size);
	printk("sector_size = %d\n",fs.sector_size);      

	rc = nvs_mount(&fs);
	if (rc) {
		printk("\n--ERROR: Flash Init failed--\n");
		exit(1);
	}
	else{
		printk("Successful init flash NVS.\n");
	}

	NVSRead();
	NVSWrite();
	NVSRead();
}


void NVSRead(){
	printk("\nRead data from NVS...\n");
	uint8_t* reading;
	rc = nvs_read(&fs, HALF_HOUR_VOLUME_READ_ID, &reading, 1);
	if (rc == 1){ /* item was found, show it */
		printk("Find NVS storage data: Id = %d, reading = %d\n", HALF_HOUR_VOLUME_READ_ID, reading);
		rc = 0;
	}
	else {/* item was not found, add it */
		printk("\nNo NVS storage data found at NVS id %d.\n", HALF_HOUR_VOLUME_READ_ID);
	}
}


void NVSWrite(){
	printk("\nWrite data to NVS...\n");
	uint8_t* data = 1000;
	rc = nvs_write(&fs, HALF_HOUR_VOLUME_READ_ID, &data, 1);
	if (rc == 1){ /* item was found, show it */
		printk("Successful write data = %d to NVS id %d\n", data, HALF_HOUR_VOLUME_READ_ID);
		rc = 0;
	}
	else {/* item was not found, add it */
		printk("\n--ERROR: Failed to write data to NVS id %d\n", HALF_HOUR_VOLUME_READ_ID);
	}
}





result:

-----------------first time running-------------------
No NVS storage data found at NVS id 2

Write data to NVS...
Successful write data = 1000 to NVS id 2
Find NVS storage data: Id = 2, reading = 1000


---------------------after reset:---------------------
Find NVS storage data: Id = 2, reading = 232

Write data to NVS...
Successful write data = 1000 to NVS id 2
Find NVS storage data: Id = 2, reading = 1000

Best regards,

Liza

[Jared]

Hi,

You have an overflow in your code.uint8_t type can only hold values from 0 to 255. If you assign this 1000 then you get an overflow, which results in an incorrect value being stored.

Try changing this to for example 250 and see if that fixes your issue,

regards

Jared 

[Liza]

Hi Jared,

Thanks for your remind! I fix the problem.

Best regards,

Liza

[Liza]

Hi Jared,

I notice that the default storage_partition=32KB. Could I configure the size to like 100KB?

Best regards,

Liza