• LoRa
  • Beginner
  • 10 min
  • Serial CLI

Recipe · Beginner · LoRa

How to configure an SX1262 LoRa radio

Start from a known profile, select only settings supported by the implementation and verify the result before receive or transmit tests.

SX1262 LoRa module and chirp waveform.
Both LoRa endpoints need compatible modem settings; frequency alone is not enough.

Know what config resets

Every explicit config run resets the radio profile before asking whether you want custom settings. The pin values remain the current defaults or choices shown by the prompts.

SettingDefaultImplementation choices
Frequency868.0 MHz150–960 MHz in software; stay inside module and regional limits.
Bandwidth125 kHz125, 250 or 500 kHz.
Spreading factorSF9SF6 through SF12.
Coding rate4/74/5 through 4/8.
TX power14 dBm-9 through +22 dBm, subject to hardware and legal limits.
Preamble8 symbols6 through 65535.
Packet optionsPrivate sync 0x1424, CRC on, normal IQSync word, CRC and IQ mode are configurable.
Oscillator1.8 V TCXOXTAL or supported DIO3 TCXO voltages from 1.6 to 3.3 V.
Step 1

Open LoRa mode, then deliberately reconfigure

Use the wiring recipe first. Run config only when you are ready to rebuild the profile from its defaults.

Answer the radio prompts

  1. Choose the frequency that matches the physical module, antenna and regional band plan.
  2. Match bandwidth, spreading factor and coding rate to the other LoRa endpoint.
  3. Use a legal TX power and a preamble suitable for the link.
  4. Match sync word, CRC and IQ mode exactly.
  5. Keep 1.8 V TCXO for compatible Core1262 hardware; select 0 only for an XTAL-based module.

Software range is not RF coverage

The configuration prompt accepts 150–960 MHz because it targets SX1262 generally. The pictured Core1262-HF hardware remains an 850–930 MHz module.

Step 2

Verify the complete profile

status prints the profile, SPI/control pins and counters. airtime 16 shows how the active bandwidth, SF and CR affect a 16-byte packet.

Troubleshooting

  • Two nodes cannot communicate: compare frequency, BW, SF, CR, sync word, CRC and IQ mode line by line.
  • Setup fails after changing TCXO: restore the oscillator voltage required by the module.
  • Range is unexpectedly poor: check the antenna and physical module band before increasing power.
  • Old profile disappeared: config intentionally starts from the implementation defaults.

Next steps

  • Use RSSI and CAD to check activity with the configured frequency, bandwidth and spreading factor.
  • Open receive mode with a known transmitter using the same profile.
  • Estimate airtime before any controlled transmission and respect regional duty-cycle rules.

SX1262 configuration FAQ

Which settings must match between two nodes?

Frequency, bandwidth, spreading factor, coding rate, sync word, CRC and IQ mode must be compatible. Preamble detection must also be possible.

Does config preserve the previous profile?

No. It resets to the documented defaults before it offers custom radio settings.

Can I use 433 MHz on Core1262-HF?

No. A software frequency setting does not change its 850–930 MHz RF matching. Use hardware and an antenna designed for the target band.

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