flash_access_in_progress() preventing BLE advertising start.

[Darrew]

My app (SDK12.3.0 + S130 v2.0.1) is being prevented from advertising because flash_access_in_progress() is true (m_queue.count != 0) on ble_advertising_start (ble_advertising.c library from SDK). It sets m_advertising_pending = true but never recovers (do not see any call to sys_event_dispatch(); i.e. any sys_event to fs):

NOTE: NVM Protection (CLENR0 != 0 and MPU.PROTENSET0|1 = 0xFFFFFFFF) is enabled.

On init (after reset), why is there a flash access in progress? in other words, why is m_queue.count != 0?

EDIT: Flash operations counter (m_queue.count) seems to get incremented (at least after power-up gets 1) after:
ble_init() > peer_manager_init() > pm_init() > pds_init() > fds_init() > queue_start() in fds.c. 

EDIT2: If memory protection is disabled (UICR.CLENR0 = 0 and MPU.PROTENSET0|1 = 0) then m_queue.count=0.

[Mttrinh]

Hi,

Are you using an unmodified example from the SDK? Have you tried debugging to see where the busy function is coming from? Which fstorage module?

[Darrew]

It seems that m_queue.count = 1 and this flash operation is never performed (m_queue is a module variable in fstorage.c SDK12.3).

My app is not an unmodified example from the SDK but resembles https://github.com/NordicPlayground/nrf51-ble-micro-esb-uart where BLE advertising runs concurrent to a protocol that uses the timeslot feature of the S130.