when I start a DFU procedure the device is advertising empty packets

[M.Anis]

I'm testing the DFU as described in this link developer.nordicsemi.com/.../a00086.html after reseting in DFU mode, when I start the device discovery, I only get empty packets

bootloader.rar
ble_app_hrs.rar
nrfjprog_win.sh

[M.Anis]

please try the files now

[Hung Bui]

Hi M.Anis,

I just tested and found that the empty packet you spotted was the directed advertising ! When advertising with directed mode, the adverting data is empty, the advertising packet has only the peer address. (this is described in Testing the example manually (with Bonding) )

I think it's a bug with the bootloader now, that it will advertise in directed mode even the application has not bonded with the phone. I will check with the developer.

I'm sorry that I didn't spot this earlier.

By advertising in directed mode with no change in the address, there is a chance that the ATT table will not be refresh (no service discovery from the phone) when switching to bootloader. However it's not a problem with Master Control Panel and nRFToolbox app, because we clear the att table every time we disconnect from the application.

You can simply connect and do DFU as you did with bootloader when starting with a button press.