Hello, I have the NRF52 DK with a PCA10040 designation. As instructed, I connected the board to my computer via the USB cable. The original demo on the board worked fine with controlling the LEDs with the 4 switches. The NFC demo also worked fine.
The connecting of the DK via the USB cable resulted in the JLINK drive in my explorer. I downloaded the Heart Rate Demo and and Proximity demo to the DK by dropping them over the JLINK icon in my explorer. LED1 on the PCB did not pulsate for discovery operation and the demos do not work (the DK has a steady green LED next to the PCA10040 chip). The original demo has been erased with no way to get back to it.
I purchased 2 DK boards so I tried a second with the same results - it worked fine until I tried to download the other optional demos.
Can someone give me something to get these DKs up and running. Thank you for your comments in advance.