nRF9160 how to detect network detach?

[Bjorn191023]

Hi,

How do we detect network detach in nRF9160 in a general way?

We use lte_lc to connect which blocks until we have connect/attached to the network. But how does lte_lc indicated network detach?

BR / Björn

[jbrzozoski]

The expected method is by calling lte_lc_nw_reg_status_get.  A registration status of HOME or ROAMING means you are attached.  Note that there is some delay in falling from HOME/ROAMING back to SEARCHING after you move out of range of a tower or lose signal for some other reason.

[Bjorn191023]

jbrzozoski said:

The expected method is by calling lte_lc_nw_reg_status_get

Thanks. Is there a way to get an event when network is detached instead of polling through function lte_lc_nw_reg_status_get?

[jbrzozoski]

Currently the lte_lc library doesn't provide that.  The only way to get it is to use the at_notif library, register a handler, and make sure the CEREG notifications are enable by sending an "AT+CEREG" command to the modem.

[Lukáš]

We are facing the same issue. AT+CEREG notification won't tell you when you are disconnected immediately. In NB-IoT networks, you have to wait a few dozen seconds.