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# DifferentialPressure (UORB message)

Differential-pressure (airspeed) sensor.

This is populated by airspeed sensor drivers and used by the sensor module to calculate airspeed.
The information is published in the `SCALED_PRESSURE_n` MAVLink messages (along with information from a corresponding `SensorBaro` instance).

**TOPICS:** differential_pressure

## Fields

| Name                     | Type      | Unit [Frame] | Range/Enum | Description                                                               |
| ------------------------ | --------- | ------------ | ---------- | ------------------------------------------------------------------------- |
| timestamp                | `uint64`  | us           |            | Time of publication (since system start)                                  |
| timestamp_sample         | `uint64`  | us           |            | Time of raw data capture                                                  |
| device_id                | `uint32`  |              |            | Unique device ID for the sensor that does not change between power cycles |
| differential_pressure_pa | `float32` | Pa           |            | Differential pressure reading (may be negative)                           |
| temperature              | `float32` | degC         |            | Temperature (Invalid: NaN if unknown)                                     |
| error_count              | `uint32`  |              |            | Number of errors detected by driver                                       |

## Source Message

[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/DifferentialPressure.msg)

::: details Click here to see original file

```c
# Differential-pressure (airspeed) sensor
#
# This is populated by airspeed sensor drivers and used by the sensor module to calculate airspeed.
# The information is published in the `SCALED_PRESSURE_n` MAVLink messages (along with information from a corresponding `SensorBaro` instance).

uint64 timestamp         # [us] Time of publication (since system start)
uint64 timestamp_sample  # [us] Time of raw data capture

uint32 device_id                  # [-] Unique device ID for the sensor that does not change between power cycles
float32 differential_pressure_pa  # [Pa] Differential pressure reading (may be negative)
float32 temperature               # [degC] [@invalid NaN if unknown] Temperature
uint32 error_count                # [-] Number of errors detected by driver
```

:::
