> For the complete documentation index, see [llms.txt](https://px4.gitbook.io/px4-user-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://px4.gitbook.io/px4-user-guide/drone_parts/peripherals/barometers.md).

# Barometers

Barometers measure atmospheric pressure, and are used in drones as altitude sensors.

Most flight controller hardware on which PX4 incudes a barometer. By default PX4 will select the barometer with the highest priority (if any are present), and configure it as a data source for [Height estimation](/px4-user-guide/advanced_config/tuning_the_ecl_ekf.md#height). If a sensor fault is detected, PX4 will fall back to the next highest priority sensor.

Generally barometers require no user configuration (or thought)!

## Hardware Options

[Pixhawk standard](/px4-user-guide/drone_parts/flight_controller/autopilot_pixhawk_standard.md) flight controllers include a barometer, as do [many others](/px4-user-guide/drone_parts/flight_controller.md).

They are also present in other hardware:

* [CUAV NEO 3 Pro GNSS module](https://doc.cuav.net/gps/neo-series-gnss/en/neo-3-pro.html#key-data) ([MS5611](/px4-user-guide/development/modules_main/modules_driver/modules_driver_baro.md#ms5611))

The supported baro part numbers can be inferred from the driver names, which are listed in [PX4-Autopilot/src/drivers/barometer](https://github.com/PX4/PX4-Autopilot/tree/main/src/drivers/barometer) and from the [Modules Reference: Baro (Driver)](/px4-user-guide/development/modules_main/modules_driver/modules_driver_baro.md) documentation. At time of writing, drivers/parts include: bmp280, bmp388 (and BMP380), dps310, goertek (spl06), invensense (icp10100, icp10111, icp101xx, icp201xx), lps22hb, lps25h, lps33hw, maiertek (mpc2520), mpl3115a2, ms5611, ms5837, tcbp001ta

## PX4 Configuration

Generally barometers require no user configuration. If needed, you can:

* Enable/Disable barometers as data source for [Height estimation](/px4-user-guide/advanced_config/tuning_the_ecl_ekf.md#height) using the [EKF2\_BARO\_CTRL](/px4-user-guide/advanced_config/parameter_reference.md#EKF2_BARO_CTRL) parameter.
* Change the selection order of barometers using the [CAL\_BAROx\_PRIO](/px4-user-guide/advanced_config/parameter_reference.md#CAL_BARO0_PRIO) parameters for each baro.
* Disable a baro by setting its [CAL\_BAROx\_PRIO](/px4-user-guide/advanced_config/parameter_reference.md#CAL_BARO0_PRIO) value to `0`.

## Calibration

Barometers don't require calibration.

## Developer Information

* [Baro driver source code](https://github.com/PX4/PX4-Autopilot/tree/main/src/drivers/barometer)
* [Modules Reference: Baro (Driver)](/px4-user-guide/development/modules_main/modules_driver/modules_driver_baro.md) documentation.


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