Why the WP bit of flashbar register is always set?

[philippeloirat]

Hi everybody,

We need to program flash memory of MCF52259 but the WP bit of flashbar register is always set??

Is somebody know why and how to change it?

Thanks to your reply.

Philippe

[TomE · Accepted solution]

It is always set to prevent you from writing to the address of the FLASH. That's clearly documented in section "18.3.2 Flash Base Address Register (FLASHBAR)".

Read section "1.5.4.2 Flash Memory", or the second "Note" in "18.3.2" to see how this works.

This came up in this Forum back in May, and searching for "backdoor" will get you two pages of hits going back to .

Re: Use of back door access

Prepare to be confused by the "backdoor flash address" versus the "backdoor key access".

Tom