This project is a personal hardware design experiment: the idea is to build a modern, digital-only FPV flight controller using a microcontroller family I enjoy working with instead of following the usual STM32-based approach used by most commercial FCs.

It is made with the only intent of havinf fun designing my own FPV hardware to see how hard it is and to get experience with avionics.

Why this project exists

Most FPV flight controllers are built around STM32 microcontrollers. They work well, but they are also very standardized.

I wanted to explore a different approach using the Raspberry Pi RP2354B, a modern microcontroller with a lot of IO, onboard flash, PIO peripherals, good documentation, and a development ecosystem I already enjoy.

Betaflight has started adding support for RP2350-class microcontrollers, which makes this project especially interesting: it becomes possible to imagine a serious RP-based flight controller rather than just a simple development board or proof of concept.

Design goals

The goal is not just to make a minimal board that boots.

The goal is to design something that looks and feels like a real FPV flight controller:

Digital FPV focused
Compatible with standard 4-in-1 ESCs
Designed around Betaflight
Onboard IMU and barometer
SD-card Blackbox logging
USB-C for configuration and programming
Multiple UARTs for receiver, GPS, digital VTX, and expansion
External I2C for GPS/compass modules or sensors
Buzzer, LED, PWM, ADC, and spare IO pads
Clean power architecture with 5 V, 10 V, and 3.3 V rails
Debug access for development and board bring-up

The board is intended to be practical, but the main purpose of the project is learning, design exploration, and demonstrating embedded hardware design skills.

Main features

Planned hardware features include:

Raspberry Pi RP2354B microcontroller
Onboard flash through the RP2354 package
BMI270 IMU
BMP581 barometer
microSD card slot for Blackbox logging
USB-C connector
Battery-side 5 V and 10 V regulators
3.3 V logic rail
USB or battery-powered 5 V logic rail
Digital VTX connector
GPS connector
ESC connector for a standard 4-in-1 ESC
SWD debug connector
Buzzer output
LED output
Spare UART, PWM, ADC, I2C, and GPIO pads

Digital-only FPV design

This flight controller is designed for modern digital FPV systems.

Because of that, it does not include analog video circuitry, an analog OSD chip, or analog camera routing. OSD support is expected to be handled through the digital VTX using a UART connection.

This keeps the board more focused and avoids adding legacy video circuitry that I do not personally plan to use.

Repository structure

The repository is organized around the KiCad hardware project and the written documentation.

.
├── README.md
├── .gitignore
├── Poundering.typ
└── RP_FC
    ├── RP_FC.kicad_pro
    ├── RP_FC.kicad_sch
    ├── RP_FC.kicad_pcb
    └── RP_FC.kicad_prl

Current status

This project is still in development.

The schematic and PCB are not final, and the board has not yet been fully validated. The design may change as parts are selected, routed, reviewed, and eventually tested.

At this stage, this repository should be viewed as a design-in-progress rather than a finished flight controller ready for production or flight.

Disclaimer

This is an experimental hardware project.

It is not a certified or production-ready flight controller. Anyone using this design is responsible for reviewing, testing, and validating the hardware before connecting batteries, ESCs, motors, or propellers.

Never test motors with propellers installed during early bring-up.