Memory management unit and method of accessing an address

A method of accessing an address in physical address space using a memory management unit comprising register and control logic, the method comprising:

• accessing a physical address space, by a microprocessor controller unit comprising a program counter having a first address size, via an address bus coupled between the microprocessor controller unit and a multiplexer, wherein the microprocessor controller unit is arranged to further access the physical address space via a data bus;
• providing, by a register of the register and control logic, an extended address bus between the microprocessor controller unit and the physical address space, wherein a second address size of the register is greater than the first address size of the program counter and an output of the register and control logic is coupled to the multiplexer that provides the extended address bus via an output terminal of the multiplexer receiving, at a first terminal of the multiplexer, a value in the program counter;
• receiving, at a second terminal of the multiplexer, a value in the register of the register and control logic;
• and
• selectively providing, via the multiplexer, one of the value in the program counter and the value in the register of the register and control logic, wherein the register and control logic uses one or more of the group consisting of:
• at least one register increment function;
• a register address movement function;
• and
• a register address maintain function.

A microprocessor architecture comprising:

• a physical address space;
• a central processing unit coupled to the physical address space via a data bus, the central processing unit including a program counter having a first address size;
• and
• a memory management unit including:
• register and control logic coupled to the central processing unit via the address bus, the register and control logic arranged to support the central processing unit in accessing the physical address space via the address bus, wherein the register and control logic comprises a register having a second address size greater than the first address size;
• and
• a multiplexer having a first input terminal coupled to the central processing unit via an address bus to receive a value in the program counter, a second input terminal coupled to an output of the register and control logic to receive a value in the register of the register and control logic, and an output terminal,
• the register and control logic arranged to provide an extended address bus between the central processing unit and the physical address space via the output terminal of the multiplexer, wherein the multiplexer selectively provides, via the output terminal, one of the value in the program counter and the value in the register of the register and control logic, and wherein the register and control logic further comprises one or more of the group consisting of:
• at least one register increment function;
• a register address movement function;
• and
• a register address maintain function.