HelioRC Spring Docs "Documentation" for Helio Spring FC's Recommended resources: https://fpv-flightclub.com/proton-long-range-drone/ https://fpv-flightclub.com/6s-quadcopter-build/ Images and Wiring Diagrams in the folders Spring-V1 Spring-V2 Spring-AIO Spring-Mini Helio RC Youtube https://www.youtube.com/c/HelioRC/videos Soft-Bricked FC If IMUF flash went wrong, plugin USB and wait 5 full minutes for recovery and re-flash IMUF. If cannot enter DFU mode, temporarily short-circuit the "boot" pads while plugging in USB, it should enter DFU. Unable to flash flight-firmware via Configurator RX and USB both use same resources -- recommend soldering RX positive to 5v rail to avoid the need to disconnect RX. HelioRC / ButterFlight is defunct EmuFlight flight firmware supports the HelioRC Spring FC and derivatives.