when use the sd_ble_gatts_hvx() send data and printf() the value below
p_ble_evt->evt.gatts_evt.params.hvc.handle p_ble_evt->evt.gatts_evt.params.sys_attr_missing.hint p_ble_evt->evt.gatts_evt.params.timeout.src
use %d all the value is 17, i cann't what's meaning