Design and implementation of 8-bit RISC MCU

An 8-bit Reduced Instruction Set Computer (RISC) Micro Controller Unit (MCU) has been implemented in this paper, including the design of pipeline and critical modules. The whole design uses two-stage pipeline which enables instruction-fetching modules and instruction-executing modules to work simultaneously. Its instruction set is compatible with PIC16F87XA instruction set and it achieves the execution speed of a single-cycle instruction (except for the program transfer instruction). The design is described by Verilog HDL, simulated by Modelsim and veriflcated by FPGA. The whole system can work normally and can achieve 40MHz frequency.