The Board ID is used to identify the different targets from a Universal Hex. In this case the target represents a micro:bit version. For micro:bit V1 (v1.3, v1.3B and v1.5) the boardId is 0x9900, and for V2 0x9903.
boardId
0x9900
0x9903
The Board ID is used to identify the different targets from a Universal Hex. In this case the target represents a micro:bit version. For micro:bit V1 (v1.3, v1.3B and v1.5) the
boardIdis0x9900, and for V20x9903.