Hi,
I am trying to communicate with a NOR Flash chip through EMIF. In order to do so, I have configured and enabled the MPU as shown below.
During initialization, I initialize and enable the MPU.
However, despite all of this, the MPU generates a fault on the following line of code:
The values of the FSR and FAR are as follows:
Given that these values are within the region I defined, why is the MPU generating a fault?
The problem was as follows:
I had a lower priority region covering the same address space that I hadn't enabled. By enabling this region, the faults disappeared. It seems that when MPU regions overlap, the enable/disable of the lower priority region actually supersedes that of the higher priority region (?). This perplexing behavior caused the issue. To complicate it further, disabling region 15 and keeping region 5 enabled did not generate any faults, so it seems the former really is true.
If you are experiencing the same issue, check whether your MPU regions overlap, and if they do, ensure they are all enabled.
