J-flash secure chip

[roger.k]

Hi. I just started with nRF52840.

When I use J-flash for STM, normally it proveds 'secure chip' as below.

But when I choose nRF52840, I can't see 'secure chip' activated as below..

How can I activate it?

I need your help.

[Hung Bui]

Hi Kwak,

I don't think we support the "Secure Chip" feature on JFlash, it's a feature on ST chip.

On our chip you can activate protection of SWD access by using APPROTECT, this requires you to write to a register in the UICR. Please have a look at section 4.8 in the nRF52840 Product Spec and look for APPROTECT. The only way to disable APPROTECT is to issue an erase all to the chip.

[roger.k]

Dear Hung Bui. Thank you very much.