This post describes an easy and cheap way of adding a USB serial port to a Walkera RX2634H (QR Ladybird) or RX2635H (Hoten-X) RC quadcopter receiver board. This makes it very easy to update these controllers with new software (especially when using UP42)
The used USB to serial board uses a CP2102 from Silicon Labs. Such boards are cheap and easy available on platforms like ebay or amazon. The board is also very light (~2 gramms) so that it can be permanently installed on the receiver without impairing flight performance.
