3.5 Disable Cellular Functionality
As soon as power is applied to the NL-SWNDK, the Skywire
Nano will boot up, and attempt to connect to the cellular
network using the on-board soldered-down SIM by default.
Since the soldered-down SIM is not currently activated, the
modem should be unable to connect to the network. This will
trigger the automatic backoff sequence on the modem, which
delays the next network connection for a certain amount of time
as per GSMA standards.
After the backoff timer expires, the modem will attempt to connect to the network once
more. If the connection fails again, the timer is reset for a longer period of time, and the
process continues.
To prevent subsequent failed connections while the modem's soldered-down SIM is
inactive, the modem's cellular functionality should be disabled temporarily. Type the
following command:
AT+CFUN=4
followed by the Enter key, and the modem should respond with:
OK
3.6 Set the Desired SIM Interface
By default, the modem uses the soldered-down SIM card. However, users can swap
between the soldered-down SIM card, and the external SIM interface on the NL-SWNDK
using the AT#SIMSELECT command.
Note: The #SIMELECT setting is saved by the modem, and will persist across reboots.
To use the external SIM card connector with a compatible SIM card of your choice, type
the command:
AT#SIMSELECT=1
followed by the Enter key, and the terminal should respond with:
OK
To use the onboard solder-down SIM chip, type the command:
AT#SIMSELECT=0
followed by the Enter key, and the terminal should respond with:
OK
PN 1002398 rev 1
© NimbeLink Corp. 2020. All rights reserved.
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