why I get m_evt_schedule_func error 4

[makouda]

each time my program start, I get the error m_evt_schedule_func error 4

what's the cause of this error? is it because I spend lot of time on the handler??? the handler running long task

[Ole Bauck]

The reason is probably that the scheduler queue size is full, therefore app_sched_event_put(...) will return NRF_ERROR_NO_MEM because APP_SCHED_QUEUE_FULL() returns true. The reason is probably that too many app_timer timeouts happens while the you are doing something in the handler (you said you are spending a lot of time in the handler). You can increase the APP_TIMER_OP_QUEUE_SIZE to increase the queue size. If you still are getting the error you need to spend less time in the handler somehow.

[makouda]

you're right, I could check that APP_SCHED_QUEUE_FULL return true, I raised the size of the schceculaer, now it happens less but still happening (APP_SCHED_QUEUE_FULL still return true but less frequeent)??