【正文】 16位單片機[M]. 北京：北京航空航天大學(xué)出版社，2001.[7] 左玉蘭,馬宗龍. 直流電機調(diào)速系統(tǒng)的單片機控制[J]. 集成電路應(yīng)用，1999.　[8] 王福瑞. 單片微機測控系統(tǒng)設(shè)計大全[M]. 北京：北京航空航天大學(xué)出版社，1999.[9] 張萌，和湘，. 清華大學(xué)出版社.[10] . 清華大學(xué)出版社.[11] [M]. 北京：機械工業(yè)出版社，1991.[12] 李智奇,白小平. MSP430系列超低功耗單片機原理與系統(tǒng)設(shè)計[M] 西安：西安電子科技大學(xué)出版社，2008.[13] 謝興紅. MSP430單片機基礎(chǔ)與實踐[M].北京：北京航空航天大學(xué)出版社，2008.[14] Boudreaux RR,Nelms Rm,Hung John and Modeling of a DCDCcontl Dlled by ans –bit microcontroller[A].IEEE .[15] Shyu JL,Liang T J and Chen J PWM inverter modulated by multirandom technique with fixed witching frequency[J].IEE procElectr power APpl,148(1):6268.致謝本文是在張育軍老師的精心指導(dǎo)下完成的。論文從選題到完成的整個過程中，得到了張育軍老師的熱情幫助和精心指導(dǎo)。張老師授嚴(yán)謹(jǐn)?shù)闹螌W(xué)態(tài)度、淵博的專業(yè)知識、精益求精的精神給我留下了深刻的印象，并對我的學(xué)習(xí)產(chǎn)生極大地促進作用。在此，還要感謝大學(xué)所有電氣老師在我學(xué)習(xí)中給予的幫助和支持。在論文完成之際，我還要感謝所有任課老師和教輔人員對我在學(xué)習(xí)和生活中的關(guān)心和教誨，特向他們的精心授業(yè)和辛勤工作，表示深深的敬意和感謝！本文在寫作過程中參考了大量的文獻資料，主要文獻資料已經(jīng)列出來，本文的有些句子或段落引自這些參考文獻，在此向所有的作者表示深深的感謝。附錄AThe Introduction of AT89C51DescriptionThe AT89C51 is a lowpower, highperformance CMOS 8bit microputer with 4K bytes of Flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel’s highdensity nonvolatile memory technology and is patible with the industrystandard MCS51 instruction set and pinout. The onchip Flash allows the program memory to be reprogrammed insystem or by a conventional nonvolatile memory programmer. By bining a versatile 8bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a powerful microputer which provides a highlyflexible and costeffective solution to many embedded control applications.Function characteristicThe AT89C51 provides the following standard features: 4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16bit timer/counters, a five vector twolevel interrupt architecture, a full duplex serial port, onchip oscillator and clock circuitry. In addition, the AT89C51 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The Powerdown Mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset.Pin DescriptionVCC：Supply voltage.GND：Ground.Port 0Port 0 is an 8bit opendrain bidirectional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as highimpedance 0 may also be configured to be the multiplexed loworder address/data bus during accesses to external program and data memory. In this mode P0 has internal 0 also receives the code bytes during Flash programming,and outputs the code bytes during programverification. External pullups are required during programverification.Port 1Port 1 is an 8bit bidirectional I/O port with internal Port 1 output buffers can sink/source four TTL 1s are written to Port 1 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally being pulled low will source current (IIL) because of the internal 1 also receives the loworder address bytes during Flash programming and verification.Port 2Port 2 is an 8bit bidirectional I/O port with internal Port 2 output buffers can sink/source four TTL 1s are written to Port 2 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 2 pins that are externally being pulled low will source current, because of the internal 2 emits the highorder address byte during fetches from external program memory and during accesses to external data memory that use 16bit addresses. In this application, it uses strong internal pullupswhen emitting 1s. During accesses to external data memory that use 8bit addresses, Port 2 emits the contents of the P2 Special Function 2 also receives the highorder address bits and some control signals during Flash programming and verification.Port 3Port 3 is an 8bit bidirectional I/O port with internal Port 3 output buffers can sink/source four TTL 1s are written to Port 3 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 3 pins that are externally being pulled low will source current (IIL) because of the 3 also serves the functions of various special features of the AT89C51 as listed below:Table 1 The second function of P3 portPort PinAlternate FunctionsRXD (serial input port)TXD (serial output port) (external interrupt 0) (external interrupt 1)T0 (timer 0 external input)T1 (timer 1 external input) (external data memory write strobe)(external data memory read strobe)Port 3 also receives some control signals for Flash programming and verification.RSTReset input. A high on this pin for two machine cycles while the oscillator is running resets the device.ALE/PROGAddress Latch Enable output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash normal operation ALE is emitted at a constant rate of 1/6 the oscillator frequency, and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory.If desired, ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALEdisable bit has no effect if the microcontroller is in external execution mode.PSENProgram Store Enable is the read strobe to external program the AT89C51 is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.EA/VPPExternal Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external pro