User's Manual

7
A. Uplink sequence
Just after powering up, SNT sends a SIGFOX message every 10 minutes by default.
This option can be set by AT commands. This message contains GPS information if
available.
When SNT is sending, green led is blinking.
Between two messages, SNT led can be of one of these two colours:
Green if internal GPS is fixed
Orange if it is not the case
B. Bidirectional sequence
In this mode the device is sending and receiving frames. The LED colour is pink.
The sequence is:
1. TX : device sending an uplink message.
2. IDLE: device in wait state (20 seconds)
3. RX: device in receive mode (timeout after 25 seconds)
Depending on the reception result, there are two possible cases:
> case 1: sequence completion by successful downlink frame reception
4. Led blinking in green, indicating successful message reception and send an
OOB message
5. Link quality indication is displayed for 10sec (details below)
Or
> case 2: sequence completion timeout after 25 secs (NO frame received)
4. LEDs blinking in RED 3 times (~6seconds)
Link quality indication:
Providing the Backend direct callback is used and includes uplink RSSI, the link quality
is flashed using a LED code:
LINK QUALITY = VERY GOOD Blinks 3 times (WHITE)
LINK QUALITY = GOOD Blinks 2 times (WHITE)
LINK QUALITY = AVERAGE Blinks 1 time (WHITE)
Note: The white LED may appear slightly pink.