Invalidating the warranty…
I wanted the RAK811 LPWAN Evaluation Board(EVB) -AS923 to work with selection of my Arduino and nanoFramework devices. The first decision was which of the hardware serial port (D0,D1) or the software serial port (D10,D11) should be connected to P1?
To use the EVB with my STM32F691DISCOVERY board running the nanoFramework (COM5 on the hardware serial port pins D0,D1) I removed R17&R19.
I can still run the Arduino Uno R3 and RAK811 EVB in the original configuration with a couple of jumper leads
After debugging some code I also replaced the small jumpers on P1 with a couple of jumper leads so it was less fiddly to swap from downloading to debugging.