Unknown USB device (device descriptor request failed)

[john.liu]

Hi:

I use nRF5_SDK_16.0.0_98a08e2\examples\peripheral\usbd_ble_uart_freertos.Error:Unknown USB device (device descriptor request failed).

I use nRF5_SDK_15.2.0_9412b96\examples\peripheral\usbd_ble_uart_freertos.nRF52 USB CDC BLE Demo This is OK.

So I continue to test sdk15.3.The result is also Unknown USB device (device descriptor request failed).

Why is that? It's a strange question.

Use PC windows10.

Maybe I can't use a PC that has registered nRF52 USB CDC BLE again.Because I used it before nRF5_SDK_15.2.0_9412b96\examples\peripheral\usbd_ble_uart_freertos.

[Jared]

Hi,

I tried the example from SDK 16 and it worked fine. Are you using a custom board or a development kti? Have you tried erasing the flash before you write with nrfjprog:

nrfjprog -e

regards

Jared