Waveshare NRF52840 - Page 28

NRF52840 Eval Kit User Manual
Vision: V1.0.1 Date: 2019.01.19 28 / 72
【Note】In official SDK, CPRTS is defined as P0.05, however, CPRTS is connected to
P0.25 on NRF52840 Eval kit. You need to modify the definition to P0.25 when using.