Is ACL configuration ONCE PER BOOT or ONCE EVER?

[kubark42]

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fps_nrf52840%2Facl.html&cp=3_0_0_5_2 states that "This register can only be written once." I am confused if this is "once ever" or "once per boot". Before I start poking at those bits, and possibly permanently bricking hardware, I'd like to know how to interpret that.

BTW, if the true intention is "once ever", then this should be made very clear in the docu. I might suggest "this register can only be written once across the life of the chip".

[Turbo J]

From the PS: "The ADDR, SIZE, and PERM registers can only be written once. All ACL configuration registers are cleared on reset. "

In other words: The register can be written once per reset.