LMIC Node, dropped packets?

[tweil]

@brandonbyrne

I worked through most of my problems; the gateway dmesg errors were from the Multitech built in network server and poly_pkt_fwd fighting over control of the MTAC card.

LMIC library had to have channels pretty explicitly forced, these are the settings I ended up with that have it receiving every packet.

LMIC_selectSubBand(1);
//Disable FSB1, channels 0-7
for (int i = 0; i < 7; i++) {
    if (i != 10)
    LMIC_disableChannel(i);
  
}
//Disable FSB2-8, channels 16-72
for (int i = 16; i < 73; i++) {
    if (i != 10)
    LMIC_disableChannel(i);
  
}

LMIC_setAdrMode(0);
LMIC.dn2Dr = DR_SF10;

// Set data rate and transmit power for uplink (note: txpow seems to be ignored by the library)
LMIC_setDrTxpow(DR_SF10,23);

// Start job
do_send(&sendjob);

selectSubBand(1) wasn’t enough to make it stay on ttn’s default of FSB 2; it would transmit on channel 8,9,10,11,12,13,14 then jump to channel 64,65,66,67,68,69,70,71 and repeat 64,65,66,67,68,69,70,71. I had to manually disable every channel but 8 through 15, as well as disable ADR(ADR was causing it to jump to 64,65,66,67,68,69,70,71 as well and get stuck there).

Getting much closer…
I tried implementing something similar to this. Before I update the code on the node, I noticed that the 9 Uplink frequencies listed in the TTN US Frequency Plan https://www.thethingsnetwork.org/docs/lorawan/frequency-plans.html#us902-928 translated to channels 8-15 and 65 using the following table which may or may not be correct. I could not find a reference to it elsewhere.
https://forum.pycom.io/topic/393/lorawan-915mhz-in-the-us/3

I used the following code to enable only channels 8-15 and 65 and had better, but not perfect results. During the JOIN process, the node continued to try frequencies that had been disabled by the code and not in the TTN US Frequency Plan (See the Serial Monitor Logs). When the node eventually tried to JOIN with a frequency in the TTN US Frequency Plan, it was successful right away. From that point on, all Uplinks sucessfully used only the frequencies in the TTN US Frequency Plan that I had specified in the code. The Uplink packets started to populate the Gateway Traffic and Application Data logs immediately, and there were no missed frames. In the Gateway Traffic log, you can see the Uplink packets start immediatley after the JOIN.

I need to try this a few more times and see if it consistently works this way. Are there other changes I should make to the code?

See logs and code below:

// LMIC init
os_init();

// Reset the MAC state. Session and pending data transfers will be discarded.
LMIC_reset();

// relaxed the timing
LMIC_setClockError(MAX_CLOCK_ERROR * 1 / 100);

LMIC_selectSubBand(1);

//Disable FSB1, channels 0-7
for (int i = 0; i <= 7; i++) 
{
LMIC_disableChannel(i); 
} 

//Disable channels 16-64
for (int i = 16; i <= 64; i++) 
{
LMIC_disableChannel(i);
}

//Disable channels 66-72
for (int i = 66; i <= 72; i++) 
{
LMIC_disableChannel(i);
}

LMIC_setAdrMode(0);
LMIC.dn2Dr = DR_SF10;

// Set data rate and transmit power for uplink (note: txpow seems to be ignored by the library)
LMIC_setDrTxpow(DR_SF10,23);

// Start job
do_send(&sendjob);

Click to see Serial Monitor logs with frequencies used

> Starting
> 15492: engineUpdate, opmode=0x8
> Packet queued
> 18547: engineUpdate, opmode=0xc
> 20899: TXMODE, freq=902300000, len=23, SF=7, BW=125, CR=4/5, IH=0
> Packet queued
> 331346: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 393007: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 402644: engineUpdate, opmode=0xc
> 444577: engineUpdate, opmode=0xc
> 444877: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 755341: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 817001: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 826639: engineUpdate, opmode=0xc
> 1000727: engineUpdate, opmode=0xc
> 1001029: TXMODE, freq=914100000, len=23, SF=8, BW=125, CR=4/5, IH=0
> 1315366: RXMODE_SINGLE, freq=925100000, SF=8, BW=500, CR=4/5, IH=0
> 1378122: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 1387695: engineUpdate, opmode=0xc
> 1388380: engineUpdate, opmode=0xc
> 1388683: TXMODE, freq=907800000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 1699197: RXMODE_SINGLE, freq=925100000, SF=7, BW=500, CR=4/5, IH=0
> 1760856: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 1770429: engineUpdate, opmode=0xc
> 2261287: engineUpdate, opmode=0xc
> 2261589: TXMODE, freq=907100000, len=23, SF=9, BW=125, CR=4/5, IH=0
> 2581783: RXMODE_SINGLE, freq=923300000, SF=9, BW=500, CR=4/5, IH=0
> 2644475: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 2653984: engineUpdate, opmode=0xc
> 2661842: engineUpdate, opmode=0xc
> 2662144: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 2972610: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 3034270: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 3043918: engineUpdate, opmode=0xc
> 3876355: engineUpdate, opmode=0xc
> 3876657: TXMODE, freq=902300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 4207284: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 4269849: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4279422: engineUpdate, opmode=0xc
> 4321010: engineUpdate, opmode=0xc
> 4321311: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 4631777: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 4693437: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4702946: EV_JOIN_FAILED
> 4702975: engineUpdate, opmode=0xc
> 4725137: engineUpdate, opmode=0xc
> 4725438: TXMODE, freq=911300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 5056002: RXMODE_SINGLE, freq=926300000, SF=10, BW=500, CR=4/5, IH=0
> 5118566: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5128139: engineUpdate, opmode=0xc
> 5150168: engineUpdate, opmode=0xc
> 5150470: TXMODE, freq=911000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 5460937: RXMODE_SINGLE, freq=926300000, SF=7, BW=500, CR=4/5, IH=0
> 5522596: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5532170: EV_JOIN_FAILED
> 5532199: engineUpdate, opmode=0xc
> 5676291: engineUpdate, opmode=0xc
> 5676592: TXMODE, freq=911900000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 6007220: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 6015601: EV_JOINED
> 6015629: engineUpdate, opmode=0x808
> 6016094: TXMODE, freq=903900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> 6100433: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 6163061: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 6167434: EV_TXCOMPLETE (includes waiting for RX windows)
> 6167478: engineUpdate, opmode=0x900
> 7417478: engineUpdate, opmode=0x908
> 7417937: TXMODE, freq=904100000, len=26, SF=10, BW=125, CR=4/5, IH=0
> 1699197: RXMODE_SINGLE, freq=925100000, SF=7, BW=500, CR=4/5, IH=0
> 1760856: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 1770429: engineUpdate, opmode=0xc
> 2261287: engineUpdate, opmode=0xc
> 2261589: TXMODE, freq=907100000, len=23, SF=9, BW=125, CR=4/5, IH=0
> 2581783: RXMODE_SINGLE, freq=923300000, SF=9, BW=500, CR=4/5, IH=0
> 2644475: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 2653984: engineUpdate, opmode=0xc
> 2661842: engineUpdate, opmode=0xc
> 2662144: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 2972610: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 3034270: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 3043918: engineUpdate, opmode=0xc
> 3876355: engineUpdate, opmode=0xc
> 3876657: TXMODE, freq=902300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 4207284: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 4269849: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4279422: engineUpdate, opmode=0xc
> 4321010: engineUpdate, opmode=0xc
> 4321311: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 4631777: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 4693437: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4702946: EV_JOIN_FAILED
> 4702975: engineUpdate, opmode=0xc
> 4725137: engineUpdate, opmode=0xc
> 4725438: TXMODE, freq=911300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 5056002: RXMODE_SINGLE, freq=926300000, SF=10, BW=500, CR=4/5, IH=0
> 5118566: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5128139: engineUpdate, opmode=0xc
> 5150168: engineUpdate, opmode=0xc
> 5150470: TXMODE, freq=911000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 5460937: RXMODE_SINGLE, freq=926300000, SF=7, BW=500, CR=4/5, IH=0
> 5522596: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5532170: EV_JOIN_FAILED
> 5532199: engineUpdate, opmode=0xc
> 5676291: engineUpdate, opmode=0xc
> 5676592: TXMODE, freq=911900000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 6007220: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 6015601: EV_JOINED
> 6015629: engineUpdate, opmode=0x808
> 6016094: TXMODE, freq=903900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> 6100433: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 6163061: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 6167434: EV_TXCOMPLETE (includes waiting for RX windows)
> 6167478: engineUpdate, opmode=0x900
> 7417478: engineUpdate, opmode=0x908
> 7417937: TXMODE, freq=904100000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 7503620: RXMODE_SINGLE, freq=923900000, SF=10, BW=500, CR=4/5, IH=0
> 7566249: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 7570685: EV_TXCOMPLETE (includes waiting for RX windows)
> 7570730: engineUpdate, opmode=0x900
> 8820729: engineUpdate, opmode=0x908
> 8821188: TXMODE, freq=904300000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 8906872: RXMODE_SINGLE, freq=924500000, SF=10, BW=500, CR=4/5, IH=0
> 8969501: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 8974012: EV_TXCOMPLETE (includes waiting for RX windows)
> 8974057: engineUpdate, opmode=0x900
> 10224057: engineUpdate, opmode=0x908
> 10224517: TXMODE, freq=904500000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 10310073: RXMODE_SINGLE, freq=925100000, SF=10, BW=500, CR=4/5, IH=0
> 10372701: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 10377074: EV_TXCOMPLETE (includes waiting for RX windows)
> 10377122: engineUpdate, opmode=0x900
> 11627121: engineUpdate, opmode=0x908
> 11627581: TXMODE, freq=904700000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 11713139: RXMODE_SINGLE, freq=925700000, SF=10, BW=500, CR=4/5, IH=0
> 11775766: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 11780138: EV_TXCOMPLETE (includes waiting for RX windows)
> 11780186: engineUpdate, opmode=0x900
> 13030187: engineUpdate, opmode=0x908
> 13030647: TXMODE, freq=904900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 13116204: RXMODE_SINGLE, freq=926300000, SF=10, BW=500, CR=4/5, IH=0
> 13178831: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 13183203: EV_TXCOMPLETE (includes waiting for RX windows)
> 13183251: engineUpdate, opmode=0x900
> 14433252: engineUpdate, opmode=0x908
> 14433712: TXMODE, freq=905100000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 14519269: RXMODE_SINGLE, freq=926900000, SF=10, BW=500, CR=4/5, IH=0
> 14581896: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 14586268: EV_TXCOMPLETE (includes waiting for RX windows)
> 14586316: engineUpdate, opmode=0x900
> 15836317: engineUpdate, opmode=0x908
> 15836777: TXMODE, freq=905300000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 15922333: RXMODE_SINGLE, freq=927500000, SF=10, BW=500, CR=4/5, IH=0
> 15984961: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 15989333: EV_TXCOMPLETE (includes waiting for RX windows)
> 15989381: engineUpdate, opmode=0x900
> 17239381: engineUpdate, opmode=0x908
> 17239856: TXMODE, freq=903900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 17325412: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 17388041: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 17392413: EV_TXCOMPLETE (includes waiting for RX windows)
> 17392461: engineUpdate, opmode=0x900
> 18642462: engineUpdate, opmode=0x908
> 18642922: TXMODE, freq=904100000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued

Here is another test using the same code that has the odd behavior of mulitple successful JOINs before the Uplink packets.

Click to see Serial Monitor logs with frequencies used

> Starting
> 230: engineUpdate, opmode=0x8
> Packet queued
> 2311: engineUpdate, opmode=0xc
> 4599: TXMODE, freq=902300000, len=23, SF=7, BW=125, CR=4/5, IH=0
> Packet queued
> 315109: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 376769: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 386407: engineUpdate, opmode=0xc
> 422264: engineUpdate, opmode=0xc
> 422565: TXMODE, freq=903000000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 733028: RXMODE_SINGLE, freq=923300000, SF=7, BW=500, CR=4/5, IH=0
> 794688: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 804326: engineUpdate, opmode=0xc
> 855060: engineUpdate, opmode=0xc
> 855361: TXMODE, freq=914300000, len=23, SF=8, BW=125, CR=4/5, IH=0
> 1169826: RXMODE_SINGLE, freq=925700000, SF=8, BW=500, CR=4/5, IH=0
> 1232582: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 1242155: engineUpdate, opmode=0xc
> 1303846: engineUpdate, opmode=0xc
> 1304147: TXMODE, freq=909400000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 1614613: RXMODE_SINGLE, freq=925700000, SF=7, BW=500, CR=4/5, IH=0
> 1676274: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 1685847: engineUpdate, opmode=0xc
> 2080700: engineUpdate, opmode=0xc
> 2081003: TXMODE, freq=903100000, len=23, SF=9, BW=125, CR=4/5, IH=0
> 2401261: RXMODE_SINGLE, freq=925700000, SF=9, BW=500, CR=4/5, IH=0
> 2463953: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 2473525: engineUpdate, opmode=0xc
> 2478667: engineUpdate, opmode=0xc
> 2478969: TXMODE, freq=909400000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 2789499: RXMODE_SINGLE, freq=925700000, SF=7, BW=500, CR=4/5, IH=0
> 2851159: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 2860807: engineUpdate, opmode=0xc
> 3849846: engineUpdate, opmode=0xc
> 3850148: TXMODE, freq=909300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 4180712: RXMODE_SINGLE, freq=925100000, SF=10, BW=500, CR=4/5, IH=0
> 4243276: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4252849: engineUpdate, opmode=0xc
> 4268387: engineUpdate, opmode=0xc
> 4268689: TXMODE, freq=907800000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 4579155: RXMODE_SINGLE, freq=925100000, SF=7, BW=500, CR=4/5, IH=0
> 4640815: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 4650388: EV_JOIN_FAILED
> 4650417: engineUpdate, opmode=0xc
> 4714564: engineUpdate, opmode=0xc
> 4714865: TXMODE, freq=911700000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 5045493: RXMODE_SINGLE, freq=927500000, SF=10, BW=500, CR=4/5, IH=0
> 5108058: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5117631: engineUpdate, opmode=0xc
> 5171754: engineUpdate, opmode=0xc
> 5172055: TXMODE, freq=914200000, len=23, SF=8, BW=500, CR=4/5, IH=0
> 5482521: RXMODE_SINGLE, freq=927500000, SF=7, BW=500, CR=4/5, IH=0
> 5544181: RXMODE_SINGLE, freq=923300000, SF=10, BW=125, CR=4/5, IH=0
> 5553690: EV_JOIN_FAILED
> 5553719: engineUpdate, opmode=0xc
> 6181324: engineUpdate, opmode=0xc
> 6181626: TXMODE, freq=913300000, len=23, SF=10, BW=125, CR=4/5, IH=0
> 6512254: RXMODE_SINGLE, freq=927500000, SF=10, BW=500, CR=4/5, IH=0
> 6520571: EV_JOINED
> 6520598: engineUpdate, opmode=0x808
> 6521071: TXMODE, freq=903900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> 6605475: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0
> 6668103: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 6672539: EV_TXCOMPLETE (includes waiting for RX windows)
> 6672585: engineUpdate, opmode=0x900
> 7922584: engineUpdate, opmode=0x908
> 7923042: TXMODE, freq=904100000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 8008662: RXMODE_SINGLE, freq=923900000, SF=10, BW=500, CR=4/5, IH=0
> 8071291: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 8075663: EV_TXCOMPLETE (includes waiting for RX windows)
> 8075707: engineUpdate, opmode=0x900
> 9325708: engineUpdate, opmode=0x908
> 9326166: TXMODE, freq=904300000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 9411850: RXMODE_SINGLE, freq=924500000, SF=10, BW=500, CR=4/5, IH=0
> 9474479: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 9478990: EV_TXCOMPLETE (includes waiting for RX windows)
> 9479035: engineUpdate, opmode=0x900
> 10729034: engineUpdate, opmode=0x908
> 10729493: TXMODE, freq=904500000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 10815050: RXMODE_SINGLE, freq=925100000, SF=10, BW=500, CR=4/5, IH=0
> 10877678: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 10882051: EV_TXCOMPLETE (includes waiting for RX windows)
> 10882098: engineUpdate, opmode=0x900
> 12132098: engineUpdate, opmode=0x908
> 12132558: TXMODE, freq=904700000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 12218114: RXMODE_SINGLE, freq=925700000, SF=10, BW=500, CR=4/5, IH=0
> 12280742: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 12285114: EV_TXCOMPLETE (includes waiting for RX windows)
> 12285162: engineUpdate, opmode=0x900
> 13535163: engineUpdate, opmode=0x908
> 13535623: TXMODE, freq=904900000, len=26, SF=10, BW=125, CR=4/5, IH=0
> Packet queued
> 13621178: RXMODE_SINGLE, freq=926300000, SF=10, BW=500, CR=4/5, IH=0
> 13683806: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0
> 13688179: EV_TXCOMPLETE (includes waiting for RX windows)
> 13688227: engineUpdate, opmode=0x900