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matthijskooijman / arduino-lmic

:warning: This library is deprecated, see the README for alternatives.
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Lora Node unable to receive downlink messages #281

Open sgodey opened 4 years ago

sgodey commented 4 years ago

I am using RFM95W module along with ATMega328p as an IoT node. I have a RAK2245 based gateway that is continuously sending packets at 923.3 and SF12. Below is the log output. I am dumping RSSI when ever OpMode changes. All times, I am seeing RXTIMEOut. I have been stuck at this problem for long time. Any help is greatly appreciated.

Starting RXMODE_RSSI Packet queued 1182: Opmode: 0x8b 1220: rssi: -164 dBm MdmStat: 0x10 26841: Opmode: 0x89 26882: rssi: -164 dBm MdmStat: 0x10 26989: Opmode: 0x88 27053: rssi: -164 dBm MdmStat: 0x0 83443: RXMODE_SINGLE, freq=923300000, SF=10, BW=500, CR=4/5, IH=0 83459: Opmode: 0x8e 83570: rssi: -44 dBm MdmStat: 0x4 96100: Opmode: 0x89 96142: rssi: -45 dBm MdmStat: 0x14 96245: Opmode: 0x88 96305: rssi: -164 dBm MdmStat: 0x0 140438: RXMODE_SINGLE, freq=923300000, SF=12, BW=500, CR=4/5, IH=0 140457: Opmode: 0x8e 140578: rssi: -41 dBm MdmStat: 0x4 159538: Opmode: 0x88 159582: rssi: -164 dBm MdmStat: 0x0 159662: EV_TXCOMPLETE (includes waiting for RX windows) Packet queued

matthijskooijman commented 4 years ago

Did you see and try https://github.com/matthijskooijman/arduino-lmic#problems-with-downlink-and-ota ?

sgodey commented 4 years ago

I am using 10% clock correction.

LMIC_setClockError(MAX_CLOCK_ERROR * 10 / 100);

And my RX2 settings are 923.3 MHz, BW500 and SF12. I am using util_tx_continous from https://github.comLora-net/lora-gateway, to generate a continuous stream of Lora packets at Freq-923.3, BW-500, SF12.

kangyang73 commented 4 years ago

Does it work? I also have same problems.

sgodey commented 4 years ago

Does it work? I also have same problems.

It worked for me. My problem was ...

  1. Not properly aligning the channel frequencies/SF/BW between transmitter and receiver.
  2. The packet format between tx and rx was little bit different (receiver was expecting explicit header and transmitter was sending implicit header)

Once I fixed those and use the LMIC_setClockError, it worked for me.

mrx23dot commented 2 years ago

Please close issue.