1. CLI Upgrades and Channel Mapping

Over the past 5 days, I knocked out some major quality-of-life upgrades for the flight controller. I added customizable channel mapping for CRSF directly through the CLI. By utilizing a combination of references and pointers, I was able to point a volatile alias to certain channel mappings, allowing for completely customizable CRSF channels. While I was in the CLI logic, I also added the ability to configure custom IMU orientations around the z-axis, making it way easier to mount the board in different directions without having to recompile the firmware.

2. DMA Pipeline Fixes and Baro Optimization

A big chunk of this session went into debugging and refactoring the hardware data pipelines. I adjusted the ADC population pipeline in order to fix some stream parsing issues, and gave the barometer a massive overhaul. The baro now uses a non-blocking, non-circular DMA setup that relies on a semi-interrupt-driven task call rather than a continuous loop. This enabled me to yield in the middle of the function, and call back later as soon as DMA is finished transferring. I also fixed a massive bug in the DMA setup: the DMA_SxCR_HTIE and DMA_SxCR_TCIE flags were accidentally enabled for the GPS and OSD ring buffers, which would have crashed the whole RTOS by firing unhandled interrupts, causing default HAL and IRQ handlers to run.

3. Walksnail Two-Way Communication

Finally, I built out the respondToVTX task to get the drone properly communicating with the Walksnail VTX. Instead of just blindly sending video data out, this sets up true two-way communication over asynchronous UART. By writing a persistent byte-by-byte state machine, the flight controller can now safely parse incoming requests from the VTX without dropping half-packets, allowing me to send back live stick positions and armed status for the OSD menus.

The only thing left to do now is handle persistent CLI storage, the logToBlackBox task, integrating the semi-interrupt pipeline with telemetryTX and the OSD, and a few other system tweaks. After that the RTOS will be 100% ready to fly the actual drone.