Mass erase, voltage interruption and FSEC

[luca_toso]

Hi All, 

let's assume that we have enabled security on the device, but leaving mass erase enabled. 

What happens if we launch the command and after some ms we abruptly interrupt the voltage? 

Is it possible that with a timed interruption only the first flash sector is erased and the next POR cycle the FSEC status allows the jtag/swd debugger to connect and perform readback of the remaining program code?

K.R.

Luca.

[danielmartynek · Accepted solution]

Hi Luca,

The security is released once it has been verified that all the memory has been erased.

If only the first sector was erased, the MCU would still be secure since SEC = 11b = secure.

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Regards,

Daniel