I have nrf52840DK less than 6 month. It has been sitting in my drawer and has some sample code in it which is detecting button press and light up corresponding leds.
Last week I try to connect to my PC but my PC cannot detect it, the board is still running though and still responds to button press according to sample code.
I have tried:
- Press and hold RESET button and switch ON for 20 seconds : Not detected
- Try different cable, different PC : Not detected
- I have another nrf52840dk board PCA10056 3.0.2, all the switch settings match and this one always get detected by my PC / JLINK
Could this be a hardware issue but why ?. Static ?.
I measure one of pin of the reset button next to USB Port (J3), the top right pin measure 0v. while my good board measures 2.99v.. This pin goes to 0v when reset button is pressed.
So I'm sure that pin must have a pull up resistor. So could this mean the bad board is stuck on reset?. but why my firmware is still running (led flashes on button press).
