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Full Parameter PDF

Overview

The PROBE parameter group (specifically PROBE_EXT or BARO_PROBE_EXT) configures the automatic hardware discovery for External Sensors.

Key Concepts

1. I2C Probing

ArduPilot supports many different barometer and compass chips. Rather than forcing the user to select the exact chip model, the firmware can "probe" the I2C bus to see which chips respond.

  • PROBE_EXT: Defines which external I2C buses or specific addresses to scan during the boot sequence.

Developer Notes

  • Library: libraries/AP_Baro, libraries/AP_Compass.
  • Usage: Usually left at default (Probe all) unless you have a specific hardware conflict.

External barometers to probe

PROBE_EXT: External barometers to probe

Description

This sets which types of external i2c barometer to look for. It is a bitmask of barometer types.

Values

  • Bitmask:

    • Bit 0: BMP085
    • Bit 1: BMP280
    • Bit 2: MS5611
    • Bit 3: MS5607
    • Bit 4: MS5637
    • Bit 5: FBM320
    • Bit 6: DPS280
    • Bit 7: LPS25H
    • Bit 8: KELLER
    • Bit 9: MS5837
    • Bit 10: BMP388
    • Bit 11: ICP10100
    • Bit 12: ICP20100
    • Bit 13: SPL06

  • Default: Varies by board (HAL_BARO_PROBE_EXT_DEFAULT)

Description

This parameter controls which barometer drivers are loaded when searching the external I2C bus.

  • Usage: If you connect an external I2C barometer (e.g., on a GPS module), this parameter determines which chips the autopilot will try to find.
  • Optimization: You can disable unused bits to speed up the boot process and prevent false detection of other I2C devices.

Source Code

ardupilot/libraries/AP_Baro/AP_Baro.cpp

Position Controller Configuration (POS) Proximity Sensor Configuration (PRX)