Softdevice protection and nordic DFU

RE: Softdevice protection and nordic DFU

AlwinG — Tue, 05 Mar 2019 10:59:29 GMT

Hi Vidar.

Yes I have nrfjprog installed.

Thanks for answering!

RE: Softdevice protection and nordic DFU

Vidar Berg — Tue, 05 Mar 2019 10:06:25 GMT

Hi,

Correct, you can enable readback protection by writing to the APPROTECT register in UICR. Unfortunately, enabling and disabling of readback protection does not seem to be supported in nRF connect yet. Do you have nrfjprog installed? The following commands are used to enable/disable readback protection:

nrfjprog --rbp all // enables readback protection by writing to UICR.APPROTECT

nrfjprog --recover // Performs a full chip erase to disable readback protection

RE: Softdevice protection and nordic DFU

AlwinG — Tue, 05 Mar 2019 09:33:05 GMT

Hi.

Now I tested it with the nRF connect app "Programmer" (V 2.6.2) and read the migration document (nrf51 to nrf52).

As you said the CLENR0 is not available on the nrf51 and the new MWU protects the softdevice.

To enable read-back I have to use the APPROTECT.

... is that correct?

According to application notes and devzone I can set the APPROTECT in FW. But how can i set this read-back with nRF connect?

If I set the read-back in nRFgo Studio, I can't read it with nRFconnect and I found no option to recover the nRF52!

RE: Softdevice protection and nordic DFU

Vidar Berg — Tue, 05 Mar 2019 07:39:46 GMT

Hi, these checkboxes are greyed out in my version of nRFGo studio (1.21.2.10). In any case, these options should not be enabled when programming 52 series, nor should they have been displayed. nRFGo studio has been replaced by the programmer app in nRF connect for desktop.

RE: Softdevice protection and nordic DFU

AlwinG — Mon, 04 Mar 2019 15:20:51 GMT

Hi Vidar,

Thanks for answering!

Yes I use nRFgo studio to load the images.

There I can check or uncheck these options (Lock SD from readback, enable SD protection, lock chip from readback).

Do they have no effect?

RE: Softdevice protection and nordic DFU

Vidar Berg — Mon, 04 Mar 2019 13:04:37 GMT

Hi Alwin,

The first two options you listed should not be available on the nRF52 series. The Softdevice is secured with the MWU peripheral, which cannot be disabled with a programming flag (Maybe you are using nRFgo studio for programming?). On the 52 series, you can lock the entire chip from readback. Readback protection will not impact DFU as it is only the Debug interface that gets disabled.