Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

ovrebekk — Tue, 28 Mar 2023 07:42:42 GMT

That's great news Anusha. I will consider the case closed then 🙂

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

anusha_14 — Tue, 28 Mar 2023 05:50:18 GMT

Hi ovrebekk

Thanks for your suggestion. After reducing the scan window to half of scan interval, flash operation works as expected.

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

ovrebekk — Thu, 23 Mar 2023 07:59:51 GMT

Hi Anusha

Having a scan window equal to the scan interval means you are trying to scan 100% of the time, and it makes sense that this would affect the scheduling of lower priority activities.

Could you try to reduce the scan window to around half and see if it improves the performance?

As an example, try a scan interval of 1600 and a scan window of 800.

Best regards
Torbjørn

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

anusha_14 — Wed, 22 Mar 2023 12:36:27 GMT

Hi ovrebekk

Thanks for your response.

In my application, the scanning parameters as defined in sdk_config.h are as follows:

NRF_BLE_SCAN_SCAN_INTERVAL: 1652

NRF_BLE_SCAN_SCAN_DURATION: 0

NRF_BLE_SCAN_SCAN_WINDOW: 1652

NRF_BLE_SCAN_MIN_CONNECTION_INTERVAL:7.5

NRF_BLE_SCAN_MAX_CONNECTION_INTERVAL: 30

NRF_BLE_SCAN_SLAVE_LATENCY: 0

NRF_BLE_SCAN_SUPERVISION_TIMEOUT: 4000

What would you recommend to change in scanning parameters to be able to perform flash operation without disabling scanning?

Regards,

Anusha

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

ovrebekk — Tue, 21 Mar 2023 09:57:43 GMT

Hi Anusha

It should be possible to scan and access flash at the same time. Scanning has higher priority than flash access, but if the flash access is delayed for a long time it will get higher priority.

The full priority table can be found here.

Do you know what the scanning parameters are?

If you are in scan mode a lot of the time it will have a larger impact on other activities, such as flash access. If you try to increase the scan interval and/or reduce the scan window this might improve the flash performance.

Best regards
Torbjørn

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

anusha_14 — Tue, 21 Mar 2023 07:57:41 GMT

Hi ovrebekk

I would like to add one more point: If I stop scanning, then writing to flash works fine. So, is it really recommended to stop scanning if we need to perform flash operations? Or can scanning be still managed while a flash operation has to occur?

Regards,

Anusha

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

anusha_14 — Mon, 20 Mar 2023 19:24:22 GMT

Hi ovrebekk ,

Thanks for your response.

Are there any other changes in the flow of your application that might be changed after you have bonded to a device?

After bonding to a device, Nordic continuously scans for advertisements of this device and connects to it if the advertisement data matches certain criteria. In the case where fstorage write times out, Nordic is not connected to the device.

Can you let me know which SDK version you are using, and if you are basing your code off of one of the standard examples?

I am using nRF5_SDK_for_Thread_and_Zigbee_v4.1.0. Yes, I have used flash_fstorage example as my reference.https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v15.0.0%2Flib_fstorage.html

Are you triggering the flash write at any particular point in the code, like after a specific Bluetooth event?

No, flash write can occur when a specific command is sent over UART to Nordic. In the case I tested, device was bonded to Nordic but not connected.

Please let me know if you need any other details to help in understanding possible cause of issue.

Regards,

Anusha

RE: Fstorage timeout error for flash write (with BLE device bonded but without actively connected)

ovrebekk — Mon, 20 Mar 2023 13:17:44 GMT

Hi Anusha

It doesn't really make sense that flash write would fail just because you have stored some bonding information through the flash library.

Are there any other changes in the flow of your application that might be changed after you have bonded to a device?

Can you let me know which SDK version you are using, and if you are basing your code off of one of the standard examples?

Are you triggering the flash write at any particular point in the code, like after a specific Bluetooth event?

Best regards
Torbjørn