Hux

Software

Bench-learning plan, superseded 2026-09-26. This page describes what the F765-Wing and the Pi 5 on the table would run for P0–P1: blink, CRSF, one wheel, a listener. The F765-Wing has no CAN bus, so it is not the robot's controller; the robot's stack is four layers — CAN actuators, a portable control core, a CAN real-time MCU, and a ROS 2 companion — in docs/software.md. What survives from this page is what lands in the control core; the Pi 5 does carry forward, in containers.

V1 scope, 2026-09-27: done means one 9.5" step, 9 of 10 from a standstill (R37); the TWO_WHEEL speed command clamps at 1.5 m/s, cruise 1.0 (R38); V1 terrain is flat + 1" sills + ~20° slopes (R40). The one-leg shift is roll plus a planned leg-length difference (2.8" at the Sheet 1 roll axes) — the sandbox's feed-forward, to be carried into the control core. Detail: docs/software.md.

Bench plan 2026-09-25
Superseded 2026-09-26
F765 / Pi 5 on hand
F765 has no CAN

On each chip

Chip	Software	Job
F765-Wing	No OS. A 1 kHz timer and a main loop, built in PlatformIO with the STM32 Arduino core.	Read both gyros. Read the Nano. Keep the mode. Send a text stream to the Pi. The PID joins this same timer later.
Pi 5	Raspberry Pi OS Lite, 64-bit. Debian 13 Trixie, kernel 6.18.	One Python 3 process. It reads the stream and prints the mode, the attitude, and the sticks.
TBS Nano RX	TBS firmware, set to CRSF.	Sticks in, telemetry back. No Hux code. Channel 1 is CRSF TX, channel 2 is CRSF RX.
ESP32	Nothing.	Stays unused. The Pi already has Wi-Fi.
Wheel driver, later	SimpleFOC on that driver's own microcontroller.	The current loop. It takes a torque number from the Wing. It does not move onto the F765 or the Pi.

Rates

1 kHz on the WingGyro samples, and later the PID and the torque command. A hardware timer. The main loop parses CRSF, tracks the mode, and writes text.

10–50 Hz on the PiRead the text. Later, cameras and pathfinding send setpoints down. The Pi never sees raw gyro samples.

10–40 kHz on the driverSimpleFOC, next to the windings, once a driver exists.

What comes off the Wing

ArduPilot is on the F765-Wing today and comes off. Its estimator and mixer assume a plane or a rover, and its arming rules will fight a balance loop. INAV and Betaflight are the same kind of program. Hux is MIT and ArduPilot is GPL-3, so the new image is not a fork. Keep the pin map: which pad is which UART, and that the two gyros are an MPU6000 and an ICM20602 on SPI. Write Hux's own startup.

First image, then the PID

When	On the Wing	On the Pi
First flash	Tilt the board, move a stick, write one text line out USB.	Open the serial port and print the line. Listen only. No torque commands.
After the balance study	The studied PID, a few more lines in that same 1 kHz timer. Not a second framework.	Still listening. Setpoints come later, after the four modes work from the stick.

The Pi does not get a real-time kernel, and it does not run ROS. Python is enough for the listener. The same process can grow a camera stream and pathfinding later. The Pi does not build or flash the Wing. That happens from the bench computer over USB, using the Wing's boot button.

Links

Wing USB → PiThe first cable. A terminal is the first display. One port, one program: the configurator and the Pi do not share it.

UART, laterWing TX to Pi RX and the other way around. Common ground. 3.3 V. This is the permanent link after USB has already shown the numbers.

Nano → Wing5 V and ground from the Wing's 5 V pad. Channel 1 to the Wing RX. Channel 2 to the Wing TX. A full UART, not the receive-only radio pad.

Pi powerThe Pi 5 has its own 5 V, 5 A supply. The Wing's 5 V regulator feeds the board and the receiver. It does not feed the Pi.

Cameras

C1 and C2 on the Wing are analog composite video into the OSD, then out the VTX pad. Both cameras have to be the same format. That path is a pilot picture later, with the horizon burned in. The stair cameras are CSI or USB on the Pi. They do not go through those pads, and they are not in this image.

Modes

PARKED

TWO_WHEEL

LEFT_ONLY

RIGHT_ONLY

The first image tracks the name. It does not balance, lift a foot, or follow a path.