Hello everyone! I’m using STM32F411 mcu with SX1272 radio as a LoRaWAN node with this LMiC library. I had to port it for F411 - change some registers, pins, ISR names etc. but it works - I’m able to see packets sent by my node in the TTN console. But after few days of debugging I’m still not able …

[image] szymonmagrian: 02E13C1B: TXMODE, freq = 33BE27A0, len = 19, SF = 07, BW = 0000007D, CR = 4/05, IH 00000000 02E1B59B: RXMODE_SINGLE, freq = 33BE27A0, SF = 07, BW = 0000007D, CR = 4/05, IH = 00000000 02E1C960: RADIO RX TIMEOUT 02E1C9AF: RXMODE_SINGLE, freq = 33D3E608, SF = 0C, BW = 000000…

Thanks for your answer! I was able to implement printing out timestamps and settings info in decimal system. I’ve also changed RX2 SF to 9 as you suggested and enabled other channels. Here are the typical debug informations for different values of clockerror: no clock error (0%) 23239: Ready fo…

[image] szymonmagrian: 67601: RADIO RX TIMEOUT … For 10%, 30% and 50% it […] lasts for about 200ms. What’s actually printing the RADIO RX TIMEOUT message? Is this related to EV_SCAN_TIMEOUT ? I cannot find the message in the library you linked to . Could it indicate it failed to switch the …

Yeah this version of LMiC didn’t have any debugging information so I’ve added most of them on my own. The RADIO RX TIMEOUT is my own message (it isn’t present in “standard” arduino_lmic library). I’ve added it to know the exact os_time of RX window end. It gets called in radio_irq_handler inside r…

I’m sure you considered all, but just in case, I guess there are a few cases for failure: Gateway transmitting using the wrong settings. (Log seems okay.) Gateway not actually transmitting at all. (Any other node to test with? Like an OTAA node.) Gateway too close to the node. Node not toggling be…

I’ve edited my previous post just before you answered so you might have not noticed it: [image] szymonmagrian: EDIT: I was also able to confirm that the gateway in fact sends downlink messages correctly. I did this by writing simple LoRa receiver firmware (pure physical LoRa without LoRaWAN) …

I think, but have not verified, that TTN might use RX2 when the uplink uses SF12. For that, TTN’s SF9 in RX2 needs less airtime than RX1, as RX1 uses the same SF as the uplink hence would need SF12. (And SF12 need twice the airtime of SF11, which needs twice the time of SF10, etc.) If true, then it …

Finally some success! I changed the uplink datarate settings to SF12: LMIC_setDrTxpow( DR_SF12, 14 ); You were right - this setting caused the TTN to schedule downlinks to RX2. Then I did tests with different setClockError values and voila! - at 30% I am consistently able to receive downlinks on …

Nice find! [image] szymonmagrian: This wrong setting was almost unnoticeable to a human during debug (1 second lasted around 1.1s) but were big enough to cause RX windows timing issues. …but would not be a huge problem for SF12, where everything takes much, much longer anyhow, so despite sta…

I have exactly the same problem. Can you help with that? Thanks for your time. Regards.

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LMiC + lora_pkt_fwd: unable to receive downlinks

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