How to change the USB iSerialNumber

[abstract1340]

Hi Nordic Teams:

I'm using Nordic Connect SDK v3.1.0 and nRF52840, I want to update USB iSerialNumber string in hid-keyboard samples.

I tried two methods but they didn't work. One was to change the 'CONFIG_USB_DEVICE_SN',

and the other was to overriding the usb_update_sn_string_descriptor function,

but neither of them took effect. can someone take a look, thanks.

[tesc]

Hi,

The USB HID keyboard sample uses a new (experimental) USB device See New USB device support for details. With that stack, by default the Serial Number is fetched from the DEVICEID register in FICR. There is a macro for Serial Number, USBD_DESC_SERIAL_NUMBER_DEFINE, but it is hard wired to the DEVICEID.

The methods that you tried were for the old stack. With the old stack, you can change the Serial Number by setting CONFIG_USB_DEVICE_SN or overriding usb_update_sn_string_descriptor(). Some samples, such as the USB HID mouse sample, still uses the old USB device stack, where those methods are available.

Regards,
Terje