4.3.11. Register 13: Process Identifier

Reading from CP15 register returns the value of the Process Identifier.

Figure 4.11. Register 13

The Process Identifier can only be accessed if the WinCe pin is at a logic “1”;that is, the WinCE Enhancements are enabled.


Only bits [31:25] are returned. The remaining 25 bits are unpredictable.

Writing to CP15 register updates the process identifier from the value in bits [31:25]. Bits [24:0] should be zero. The Process Identifier is set to 0000000 on Reset. The CRm and opcode_2 should be zero when reading or writing CP15 register 13.

Changing Process Identifier

Care must be taken when changing Process Identifier as the following instructions will have been fetched with the Process Identifier. In this respect, changing the Process Identifier has similarities with a branch with delayed execution. See Relocation of Low Virtual Addresses by Process Identifier.

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