This is one of those PCB’s that we have needed for a long time but have just been ‘getting by’ with off the shelf solutions. It’s a hardened (and tiny at 12x20mm) USB-Serial module, with secure and robust latching JST-GH connectors. One side connects (with latching non-consumer grade connectors!) to a USB host such as a PicoNV, other payload computer PC, or Android device. The other side connects to a TTL serial port (3.3V / 5V tolerant), to interface to a Pixhawk, Picoradio (it has the same pinout and connector as a Picoradio serial port), or other device such as a gimbal or payload. And you can power it from either side and pass through power to the other device if needed. No more needing to use bitbanged / software serial on a Raspberry Pi etc. when you need another serial port (an actual UART capable of buffered serial). Driver free on most systems. We finally did it. Mic drop.
