Research And Design Of 8 Bit MCU Based On RISC

Microcontroller (MCU) appears nearly 40 years, in consumer electronics, automobile electronics and industrial application areas to be widely used, along with integrated circuit system into system on chip (SOC) era, MCU not only can be used as a single chip in embedded systems, can also act as IP core integrated into VLSI, in domestic market, foreign MCU product is popular, with such broad market, due to late start and the technical weak, domestic enterprises hold less market share, so developing the MCU of independent intellectual property rights is quite important, although it appears diverse applications, single product has been unable to meet the ever-changing market needs, but the development of MCU presents the development trend of diversified and integration, no matter how the MCU application occasions product changes, the development of core modules MCU has certain stability, just making sure the system structure of the MCU, developing the basic composition modules and subsequent application development can be meet basing on the core module.This paper analyzed the PIC16C6X series product of Microchip company carefully, the paper introduces Harvard dual bus structure of separating data bus and instructions bus, based on the original sequence, adopting two-stage line structure of modified single clock cycle, improving the temporal clock frequency of the circuit, speeding up the running speed of the MCU system, where the instruction decoding and operation module uses hard logic circuit, in order to improve the speed of the market adaptability, It adopted MCU instruction system which is compatible at PIC16C6X instruction system, the whole instruction system has 35 instructions, the majority of instructions need a single cycle to be executed, the whole MCU system uses the top-down (TOP-DOWN) method to complete each module of hardware design, finishing the language description of the circuit. the software of Modelsim finishes function simulation validation, also using the DC software company to compile the circuit, and the results showed that the integrated circuit is faster than the highest clock frequency 20MHz of PIC16C6X series. Finally, through EDI of Cadence software carried out the preliminary placement and routing, the results prove MCU system to be certain practical.In order to enhance the computing power of circuit system, this paper has designed a 8 bit multiplier for MCU embedded application. This multiplier module uses improved BOOTH algorithm, through improving structure of the coding gate level circuit and compression array, getting the higer computational speed, finishing multiplier's hardware language description and compiling the circuit based on the SMIC company process with the software of DC. Results show that the speed reaches 188MHz.