.8-bit Risc Microcontroller Design And Verification

The target of this research subject is to develop an 8-bit microcontroller, which is compatible with PIC16C57 of Microchip Technology Inc. in the instruction system. The program of the MCU is downloaded into Xilinx VirtexElOO. The MCU should be tested by a wireless mouse system and its Clock frequency should not be below 20MHZ, which is the most high clock frequency of PIC16C57.This paper investigates the system architecture and the instruction system of the microcontroller PIC16C57. It is found that the clock frequency can be improved apparently by improving the PIC16C57's system architecture. Through many experiments, it is proposed to replace the two-pipeline architecture of PIC16C57 with a novel multi-cycle architecture. The multi-cycle architecture has following features: system structure is briefer and circuit design is simpler. These features result in decreasing the design errors in circuit design and making upward compatibility easier.The MCU is described by using VHDL. Many common arithmetic programs are used to test the source programs of the MCU. When the experiment result is correct and the timing simulation is also right, a verified wireless mouse receive program is run in MCU.These successful experiments declare the developed MCU is fully compatible with PIC16C57 and its system clock reaches above 60MHZ.The research subject also provides a useful system architecture: multi-cycle architecture. Its instruction cycle is made up of four clock cycles. Every instruction can be executed in one instruction cycle. This multi-cycle architecture is fit for the RISC microcontroller.