16-bit teaching microprocessor design and application

The existing commercial microprocessors are provided as black box units, with which users are unable to monitor internal signals and operation process, neither can they modify the original structure. So they are unsuitable for teaching. In order to solve this problem, the present paper designs a simplified but fully functional 16-bit teaching microprocessor using the microprogrammed control method. The microprocessor is easy-to-modify as a VHDL and Verilog HDL modular, hierarchical description, gives access to every internal signal, and is open for user modifications. The design of ALU was optimized so that it consumes fewer resources. The microprocessor was implemented on Xilinx FPGA and has been applied in the Computer Organization and Architecture course for four years.