Flash protection with DFU on nrF52832

[Nabil]

Hello, 

I'm using : 

- SDK 11 s132

- nRF52832 

I want to protect my flash against dumping from swd but I'm working also with DFU from our custom app. 

Is it possible to update from DFU when flash is protected with APPROTECT ?

Thank you.

[Nguyen Hoan Hoang]

yes.

[Nabil]

Hello, 

I have tried it but it seem that it doesn't work. After updated the app doesn't start with protection but working very well without protection.

Thank you

[Nguyen Hoan Hoang]

I found that some times I had to DFU it twice for it to work.  I haven't found the problem yet.   DFU the first time didn't work. DFU the second time worked.

[Vidar Berg]

Hello,

APPROTECT prevents external access through the debug interface, but does not affect the CPU's access to memory internally. In other words, it shouldn't affect the DFU process. How are you enabling the readback protection, with the programmer, or from the bootloader/app?

[Vidar Berg]

Nguyen Hoan Hoang, are you using the WD timer in your app? Maybe you are seeing  a WD timeout when it fails?