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Hardware
SIM card
Digi XBee® 3 Cellular LTE-M/NB-IoT Global Smart Modem User Guide
107
PWM duty cycle
Number of LEDs turned
on
Received signal strength (dBm)
79.39% or more
3
-83 dBm or higher
62.42% to
79.39%
2
-93 to -83 dBm
45.45% to
62.42%
1
-103 to -93 dBm
Less than
45.45%
0
Less than -103 dBm, or no cellular network
connection
SIM card
The XBee Smart Modem uses a 4FF (Nano) size SIM card.
CAUTION!
Never insert or remove SIM card while the power is on!
Associate LED functionality
The following table describes the Associate LED functionality. For the location of the Associate LED on
the XBIB-CU-TH development board, see number 5 on the
LED status
Blink
timing
Meaning
On, solid
Not joined to a mobile network.
Double blink
½ second
The last TCP/UDP attempt failed. If the LED has this pattern,
you may need to check
or
(Protocol/Connection Indication)
for the cause of the error.
Note
This pattern applies only to the Transparent mode.
Other transmission modes do not affect the Associate LED
blink pattern.
Standard single blink
1 second
Normal operation.
The normal association LED signal alternates evenly between high and low as shown below:
Where the low signal means LED off and the high signal means LED on.
When
CI
is not
0
or
0xFF
, the Associate LED has a different blink pattern that looks like this: