### Install Native Platform

Source: https://www.expresslrs.org/software/testing/unit-testing

Command to install the native platform required for running tests.

```bash
pio platform install native
```

--------------------------------

### Install PlatformIO and dependencies

Source: https://www.expresslrs.org/software/toolchain-install

Install the required build tools and specific versions of Python packages.

```bash
pip install platformio dronecan setuptools empy==3.3.4 pexpect
```

--------------------------------

### Install OpenOCD on Debian/Ubuntu

Source: https://www.expresslrs.org/software/open-ocd

Use this command to install OpenOCD from your distribution's repository. Ensure you have the necessary permissions.

```bash
sudo apt-get install openocd
```

--------------------------------

### Connect TX to Telemetry Viewer (ArduPilot Example)

Source: https://www.expresslrs.org/software/airport

Instructions for connecting the TX module to a telemetry viewing program like Mission Planner or QGC, using ArduPilot as an example.

```text
Connect the TX to a computer via USB, open the program that you intend to view the telemetry in, then connect to the COM port for your TX module at the baud you entered above. For example, if using AirPort for MAVLink in ArduPilot, you would open Mission Planner / QGC etc. and select the TX COM port, enter the baud, then click Connect.
```

--------------------------------

### Setup Python virtual environment

Source: https://www.expresslrs.org/software/toolchain-install

Create and activate a local virtual environment to isolate project dependencies.

```bash
python -m venv .venv
source .venv/bin/activate
```

--------------------------------

### Install virtual-env

Source: https://www.expresslrs.org/software/toolchain-install

Ensure the virtual environment package is available for Python.

```bash
pip install virtual-env
```

--------------------------------

### Configure FC UART for AirPort (ArduPilot Example)

Source: https://www.expresslrs.org/software/airport

Example configuration for an FC UART using ArduPilot's Configurator tool for MAVLink telemetry over AirPort.

```text
Using the appropriate Configurator tool for your FC firmware, configure your selected UART with your desired telemetry protocol. For example, if using AirPort for MAVLink in ArduPilot, you would set:
  * `SERIALN_BAUD` to the baud you entered in the section above,
  * `SERIALN_OPTIONS` to `0`,
  * `SERIALN_PROTOCOL` to `1` or `2` (for MAVLink v1 or MAVLink v2).
```

--------------------------------

### Flash firmware to device

Source: https://www.expresslrs.org/software/toolchain-install

Build and upload the firmware to a specific port.

```bash
pio run --target upload --environment Unified_ESP32_900_RX_via_BetaflightPassthrough --upload-port /dev/ttyUSB0
```

--------------------------------

### ArduPilot Serial Setup with 420K Baud

Source: https://www.expresslrs.org/quick-start/ardupilot-setup

Configure ArduPilot serial port for ExpressLRS, enabling the 420K baud rate and setting RCIN protocol. This is an alternative setup if the default fails.

```ini
SERIALx_PROTOCOL = 23 (RCIN)
SERIALx_BAUD = 115
RSSI_TYPE = 3 (ReceiverProtocol)
```