mirror of
https://github.com/mikecarper/MeshCore.git
synced 2026-09-26 18:47:56 +00:00
mikecarper
b8697d7db0
Retain the original carrier feature from PR #11 with zero-deviation FSK, board PA calibration, and LoRa restoration. Re-key after power changes without extending the timeout, and restore prior power after a failed sweep. Cover native and SX1276 transitions, failure recovery, external PA and RFO mapping; verify Linkflow repeater and Heltec V2 USB Companion builds.
55 lines
3.0 KiB
Markdown
55 lines
3.0 KiB
Markdown
# Carrier-wave RF checks
|
|
|
|
`cw` and `cw2` transmit a continuous, unmodulated carrier at the selected
|
|
profile's frequency and the configured TX power. They are available in the
|
|
shared ASCII CLI on SX1276-family, SX1262-family, and LR1110 builds, including repeaters,
|
|
Companions, room servers, and sensors that use that CLI.
|
|
|
|
| Command | Action |
|
|
| --- | --- |
|
|
| `cw on` | Use the active primary frequency for 10 seconds. |
|
|
| `cw on 2.5` | Use the active primary frequency for 2.5 seconds. |
|
|
| `cw2 on 0.75` | Use the active second profile for 0.75 seconds. |
|
|
| `cw off` or `cw2 off` | Stop the carrier immediately. Either name stops it. |
|
|
| `get cw` or `get cw2` | Show which carrier is active and its remaining seconds. |
|
|
|
|
`set cw ...` and `set cw2 ...` are also accepted. Durations range from
|
|
0.001 to 60 seconds, rounded to milliseconds. The deadline runs in the main
|
|
loop, so it is not a precision pulse generator or a hardware cutoff.
|
|
|
|
`cw2` requires an active `radio2` or `tempradio2` profile in `rxtx` mode.
|
|
An `rx` or disabled second profile cannot transmit a carrier. `cw` uses
|
|
`tempradio` when that is the current primary profile. There is one physical
|
|
transmitter: a carrier uses one profile at a time and ignores the cross-TX
|
|
setting. Stop it before selecting the other carrier. Repeating `on` on the
|
|
same profile restarts the duration.
|
|
|
|
Packet transmission, reception, profile scanning, CAD, and receive recovery
|
|
checks pause during the carrier. The firmware keeps the MCU awake to service
|
|
the deadline, controls the board's external amplifier, and resumes normal
|
|
reception and profile scanning afterward. It rejects entry during a packet
|
|
or a busy radio. Profile retuning waits until the carrier stops; replacement
|
|
or expiry of the active second profile stops its carrier. Nothing about CW
|
|
is saved across reboot.
|
|
|
|
The normal `set tx <dBm>` command also works during CW for meter sweeps. It
|
|
keeps the board's power limits and PA calibration, resumes the carrier after
|
|
changing power, and does not extend the CW timeout. TX power retains its usual
|
|
saved behavior. SX1276 temporarily uses FSK with zero frequency deviation,
|
|
then rebuilds the LoRa configuration before resuming reception.
|
|
|
|
Use the local USB or BLE console for immediate replies and manual stopping.
|
|
An on-air CLI reply must wait until the carrier ends because LoRa packets
|
|
cannot transmit during the test.
|
|
|
|
A second radio on the same frequency can detect the carrier using
|
|
instantaneous RSSI. Compare readings before, during, and after transmission;
|
|
CAD and packet counters are not carrier detectors. This confirms RF activity,
|
|
not calibrated output power, frequency accuracy, antenna match, or SWR.
|
|
Afterward, exchange ordinary LoRa packets to verify both RX and TX recovery.
|
|
|
|
The reproducible bench witness is `tools/hil/cw_observer.cpp`, built with
|
|
`tools/hil/cw_observer.ini` on a separate RAK4631. It never transmits on its own.
|
|
See the [hardware validation](carrier_wave_validation.md) for measured results,
|
|
reproduction steps, and the tested preamble settings.
|