OK, so here (hopefully) I have captured a complete join request from all angles…
Let’s start with the TTN Gateway Console (note there are uplinks and downlinks from other devices that work fine)…
Here is the JOIN REQUEST
Here is the JOIN ACCEPT
On the Application Console for the device, here is the ACTIVATION
I have pasted the JSON from all three transmissions here…
JOIN REQUEST
{
"gw_id": "eui-7276ff000b0324e3",
"payload": "AIAhAADwe04kGyMAAAB7TiSfts6KfHs=",
"dev_eui": "244E7B000000231B",
"lora": {
"spreading_factor": 12,
"bandwidth": 125,
"air_time": 1482752000
},
"coding_rate": "4/5",
"timestamp": "2020-01-27T15:19:05.441Z",
"rssi": 0,
"snr": 11.8,
"app_eui": "244E7BF000002180",
"frequency": 868300000
}
JOIN ACCEPT
{
"gw_id": "eui-7276ff000b0324e3",
"payload": "IGZQMaCyh3npb9UND/FHY9VIennIVM61vQtY/aqqWuQU",
"lora": {
"spreading_factor": 12,
"bandwidth": 125,
"air_time": 1810432000
},
"coding_rate": "4/5",
"timestamp": "2020-01-27T15:19:10.443Z",
"frequency": 869525000
}
DEVICE ACTIVATION
{
"time": "2020-01-27T15:19:05.437680347Z",
"frequency": 868.3,
"modulation": "LORA",
"data_rate": "SF12BW125",
"coding_rate": "4/5",
"gateways": [
{
"gtw_id": "eui-7276ff000b0324e3",
"timestamp": 3829093340,
"time": "2020-01-27T15:19:04.397995Z",
"channel": 6,
"snr": 11.8
}
]
}
Finally, here is the extract from the Kerlink Lora.log file for the packet that ends in the usual “Packet REJECTED, timestamp seems wrong, too much in advance”.
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> Received uplink message:
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> | lora uplink (40100B8D), payload 23 B, channel 868.3 MHz, crc ok, bw 125 kHz, sf 12, cr 4/5
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> | Join Request, JoinEUI 244E7BF000002180, DevEUI 244E7B000000231B, DevNonce 46751
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> | - radio (00000106)
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> | - demodulator counter 3829093340, UTC time 2020-01-27T15:19:04.397995Z, rssi -68.1 dB, snr 10.5< 11.75 <14 dB
Jan 27 15:19:04 Wirnet local1.info lorafwd[9202]: <6> Uplink message (3CF3) sent
Jan 27 15:19:05 Wirnet local1.info lorafwd[9202]: <6> Uplink message (3CF3) acknowledged in 1185.27 ms
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> Heartbeat (3D40) sent
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> Downlink message (E332) received
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> Received downlink message:
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> | lora downlink (0000E332), payload 33 B, required 1, preamble 8 B, header enabled, crc disabled, polarity inverted
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> | Join Accept
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> | - radio (00000000), channel 869.525 MHz, bw 125 kHz, sf 12, cr 4/5, power 27 dB
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> | - transmission (00000000), priority 1, on counter 3835093340
Jan 27 15:19:10 Wirnet local1.info lorad[858]: <6> Received downlink message
Jan 27 15:19:10 Wirnet local1.err lorad[858]: <3> Packet REJECTED, timestamp seems wrong, too much in advance (current=3835529449, packet=3835093340, type=0)
Jan 27 15:19:10 Wirnet local1.err lorad[858]: <3> Failed to enqueue downlink message
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> Received uplink message: transmission event (0000E332 / 00000000), status "Bad timing"
Jan 27 15:19:10 Wirnet local1.info lorafwd[9202]: <6> Downlink message (E332) acknowledged
Any support in figuring out where the timing is going wrong is highly appreciated.
Regards