US Patent 7996651 Enhanced microprocessor or microcontroller

An n-bit microprocessor device has an n-bit central processing unit (CPU); a plurality of special function registers and general purpose registers which are memory-mapped to a plurality of banks, with at least two 16-bit indirect memory address registers which are accessible by the CPU across all banks; a bank access unit for coupling the CPU with one of the plurality of banks; a data memory coupled with the CPU; and a program memory coupled with the CPU, wherein the indirect address registers are operable to access the data memory or program memory and wherein a bit in each of the indirect memory address registers indicates an access to the data memory or to the program memory.