what will cause BLE_GAP_EVT_TIMEOUT?

[kk]

HI,all!

In the funtion on_ble_evt(), there is one of the events named "BLE_GAP_EVT_TIMEOUT", can someone please tell me what situasions might cause this event? (be better to list all possiable situasions ) By the way, according to my observation, when the device's advertising time proceeds APP_ADV_INTERVAL, it will cause the event, is that right?

Looking forward to your reply, thank you!

[kk]

sorry I think i have found someting to explain this: in the ble_gap.h, the defgroup BLE_GAP_TIMEOUT_SOURCES GAP Timeout sources, there are two situasions, they are: 1.BLE_GAP_TIMEOUT_SRC_ADVERTISEMENT 2.BLE_GAP_TIMEOUT_SRC_SECURITY_REQUEST As the first one is exactly what i have found out, my question is about the second one, what will cause the second situasion, I hope you can explain it in detials, thank you!