SPRAD28 October 2022 AM2431 , AM2432 , AM2434 , AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1 , AM263P4 , AM263P4-Q1 , AM26C31 , AM26C31-EP , AM26C31M , AM26C32 , AM26C32-EP , AM26C32C , AM26C32M , AM26LS31 , AM26LS31M , AM26LS32A , AM26LS32AC , AM26LS32AM , AM26LS33A , AM26LS33A-SP , AM26LS33AM , AM26LV31 , AM26LV31E , AM26LV31E-EP , AM26LV32 , AM26LV32E , AM26LV32E-EP , AM26S10 , AM2732 , AM2732-Q1
This is a configurable fault exception that is disabled by default (can be enabled by the SHCSR register). This fault detects memory access violations to regions that are defined in the Memory Management Unit (MPU). For example, code execution from a memory region with read/write access only. Another example is when unprivileged thread mode code (such as user application or RTOS task) tries to access memory region that is marked as "privileged access only" by the MPU. Also, this fault can occur due to XN (eXecute Never) issues - whenever the processor tries to execute an instruction from a XN area.
Table 6-3 shows the behavior of accesses to each region in the memory map.
Address Range | Memory Region | Memory Type | XN | Description |
---|---|---|---|---|
0x00000000 - 0x1FFFFFFF |
Code | Normal | - | Executable region for program code. You can also put data here. |
0x20000000 - 0x3FFFFFFF |
SRAM | Normal | - | Executable region for data. You can also put code here. This region includes bit band area. |
0x40000000 - 0x5FFFFFFF | Peripheral | Device | XN | This region include bit band area |
0x60000000 - 0x9FFFFFFF | External RAM | Normal | - | Executable region for data |
0xA0000000 - 0xDFFFFFFF | External Device | Device | XN | External Device Memory |
0xE0000000 - 0xE00FFFFF | PPB - Private Peripheral Bus | Strongly-Ordered | XN | This region include the NVIC, System Timer and System Control Block |
0xE0100000 - 0xFFFFFFFF | Device | Device | XN | Implementation-specific |