4.3.5. c0, MPU Type Register

The MPUIR characteristics are:


Holds the value for the number of instruction and data memory regions implemented in the processor.

Usage constraints

The MPUIR is:

  • a read-only register

  • accessible in Privileged mode only.


Available in all processor configurations.


Figure 4.10 shows the MPUIR bit assignments.

Figure 4.10. MPUIR Register bit assignments

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Table 4.6 shows the MPUIR bit assignments.

Table 4.6. MPUIR Register bit assignments

Bits NameFunction
[15:8]DRegionSpecifies the number of unified MPU regions. Set to 0, 8 or 12 data MPU regions.

Specifies the type of MPU regions, unified or separate, in the processor.

Always set to 0, the processor has unified memory regions.

To access the MPUIR, read CP15 with:

MRC p15, 0, <Rd>, c0, c0, 4 ; Returns MPU information
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