Trying to use an nRF52-DK for nRF Connect Desktop

[euggersh]

I haven't been able to find any documentation or forum posts along the lines of the problem I'm having, so...

I'm trying to use an nRF52-DK with nRF Connect Desktop to connect to BLE peripherals for testing.  The board was previously used by someone else and has some unknown firmware on it.

When I connect my Windows PC to the board's micro USB port and turn it on, LED1 pulses and the board does not appear as a USB device in any form.

I did find a post about holding down IF BOOT/RESET while powering the board up.  If I do that, LED1 pulses, LD5 blinks, and the board appears in Windows as a removable drive.  The drive goes away after about 10 seconds, and LED1 and LD5 continue to pulse and blink respectively.

Throughout all of this, at no time does the board appear in the Programmer app in nRF Connect Desktop.

I'd appreciate some direction as to where to go from here to program firmware on this thing.

Thanks.

[Menon]

Hello,

Could you once try erasing the board by using nRF command line tool or nRF connect for Desktop? You can follow this page for doing the same. 

I did find a post about holding down IF BOOT/RESET while powering the board up.  If I do that, LED1 pulses, LD5 blinks, and the board appears in Windows as a removable drive. 

By doing this you are updating the debugger chip, this is why it shows as a removable drive(Don't know why it goes away though).

Kind Regards,

Abhijith

[euggersh]

Those instructions appeare to rely on the board being visible in Programmer.  As I said in my original post, the board never appears in Programmer.   The only time it even appears on USB in any way is in removeable drive mode.  So how can I erase it?