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Only 16 least significant bits of the counter are sent in this message, the server must take care of possible overflows. It is also important to notice, that counter information is not stored in nonvolatile memory and so it is lost in case of reboot and the counter resets to 0. The server can correctly process reboot by processing the Startup message(if Reset cause is not equal to 0, there was reboot and the counter was reset to 0).
4.2.2 Heartbeat
The heartbeat message uses port 2 and it is always confirmed. The heartbeat message is sent every 24 hours (by default).
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Byte | Bits | Name | Default value |
|---|---|---|---|
0 | 0..2 | DataRate configuration | 2 (DR2) |
3Reserved | Enable ADR(Adaptive Data Rate):
| 0 | |
4..6 | Counter update confirmation configuration | 1(Unconfirmed with 1 uplink message(0 repetitions)) | |
7 | Reserved | 0 |
DataRate configuration value | DataRate(Spreading Factor) |
|---|---|
0 | DR0 (SF12) |
1 | DR1 (SF11) |
2 | DR2 (SF10) |
3 | DR3 (SF9) |
4 | DR4 (SF8) |
5 | DR5 (SF7) |
6 | Reserved |
7 | Enable ADR(Adaptive Data Rate)Reserved |
Counter update confirmation configuration | Description |
|---|---|
0 | Confirmed(up to 8 repetitions) |
1 | Unconfirmed with 1 uplink message(0 repetitions) |
2 | Unconfirmed with 2 uplink messages(up to 1 repetition) |
3 | Unconfirmed with 3 uplink messages(up to 2 repetitions) |
4 | Unconfirmed with 4 uplink messages(up to 3 repetitions) |
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