AT89C2051单片机 毕业论文外文翻译.doc

外文资料翻译at89c2051 at89c2051 is the united states of america atmel company production of low voltage, high performance cmos 8 bit mcu, tablets containing the 2k bytes repeated erasable read-only memory program (perom) and 128bytes random data memory (ram), device using atmels high density, non-volatile memory technology, compatible with standard mcs-51 instruction system in general, sheet 8 bit cpu and flash storage unit, at89c2051 single-chip microcomputer in electronic products in a wide range of applications.internal structureat89c2051 is a 2k byte flash programmable and erasable read only memory (eeprom) low voltage, high performance 8 bit cmos microprocessor.it uses atmel high-density non-volatile memory technology manufacturing and industry standard mcs-51 instruction set and pin structure compatible.through the single chip combination of general cpli and flash memory, atmel at89c2051 is a powerful micro processor, which for many embedded control applications to provide a highly flexible and low cost solution.at89c2051 offers the following functions: standard 2k memory, 128 bytes of ram, 15 i/o, two 16 bit timer, a five vector two suspended structure, a full duplex serial port, a precision analog comparator and two optional software power save mode.free party stop cpu work but allows ram, timer / counter, serial port and interrupt system to continue.the power-down mode saves the ram content but the oscillator stops working and the prohibition of other parts of the work to the next a hardware reset.the confidentiality of the procedureat89c2051 design procedures are 2 confidential, confidential 1 is programmed, a program memory can not be erased unless a programming, the security bit 2 is programmed, program cannot be read.hardware and software developmentat89c2051 can use the following two methods and development of application systems.1, because 89c2051 internal program memory flash, and modify it inside the program is very convenient, if equipped with a programmable 89c2051 programmer.debugging personnel can use the program editing - compilation - curing - inserted into a circuit board test such repeated cycle method, for experienced mcs-51 programmers, debugging this method is not very difficult.but to do this test would not be able to understand the internal ram content and program direction and other relevant information.2, ordinary 8031/80c31 emulator simulation plug in p1.0 p1.7 and p3.0 p3.6 out simulation 2051, this method can use single-step, breakpoint debugging method, but the simulation is not true, for example, 2051 internal analog comparator function, p1, p3 export enhancement under tensile capacity etc.pin descriptionat89c2051 chip pin diagramthe at89c2051 pin diagram as shown on the right.in 1, vcc: power supply voltage.in 2, gnd.in 3, p1: p1 is a 8 bit bidirectional i/o export.port of p1.2p1.7 with internal pull-up resistor, p1.0 and p1.1 requires external pull up resistor.p1.0 and p1.1 are respectively as on-chip precision analog comparator of the in-phase input (ani0) and the inverting input (ain1).the p1 port output buffer capable of absorbing 20ma current and can directly display driver led.when the p1 port write 1, which can be used as input, when p1.2p1.7 is used as the input pins and is externally pulled low, they will because of internal write 1, which can be used as input.when the pin is p1.2p1.7 as input and is externally pulled low, they will because of internal pull-up resistor and the outflow current.in 4, p3: p3 p3.0p3.5, p3.7 mouth with internal pull-up resistor seven bidirectional i/o port.p3.6 is used for fixing the input in the output signal of the comparator and it serves as a general i/o pins that are not accessible.p3 port buffer can absorb 20ma current.when the p3 export to write 1, they are internal pull-up resistors are pulled up and used as input.as input, is externally pulled low p3 mouth foot will use the pull-up resistor and the outflow current.p3 is also used to achieve various at89c2051 second function, are listed in the following table:pin export functionp3.0 rxd serial input portp3.1 txd serial output portp3.2 int0 external interrupt 0p3.3 int1 external interrupt 1p3.4 t0 timer 0 external inputp3.5 t1 timer 1 external inputp3 also receives some for flash memory programming and verification process control signal.in 5, rst: reset input.once rst becomes the high level all the pins of the i/o is reset to 1 .when the oscillator is running, continued to give rst pin two machine cycles of high level can complete reduction.each machine cycle needs 12 oscillator or clock cycles.in 6, xtal1: as the oscillator inverter input and internal clock generator input.in 7, xtal2: as the oscillator the output of the inverting amplifier.main performancein 1, and mcs-51 compatibility;in 2, 2kb reprogrammable memory flash (10000 times);in 3, 2.7-6v voltage range;4, all static work: 0hz-24mhz;in 5, 2 level program memory security lock;in 6, 128*8 internal ram;7, 15 programmable i/o line;in 8, two and 16 timer / counter;9, 6 interrupt sources;10, programmable serial channel;in 11, and high precision voltage comparator (p1.0, p1.1, p3.6);12, direct drive led output port. at89c2051是美国atmel公司生产的低电压、高性能cmos 8位单片机，片内含2k bytes的可反复擦写的只读程序存储器（perom）和128bytes的随机数据存储器（ram），器件采用atmel公司的高密度、非易失性存储技术生产，兼容标准mcs-51指令系统，片内置通用8位中央处理器和flash存储单元，at89c2051单片机在电子类产品中有广泛的应用。at89c2051是一带有2k字节闪速可编程可擦除只读存储器（eeprom）的低电压，高性能8位cmos微处理器。它采用atmel的高密非易失存储技术制造并和工业标准mcs-51指令集和引脚结构兼容。通过在单块芯片上组合通用的cpli和闪速存储器，atmel的at89c2051是一强劲的微型处理器，它对许多嵌入式控制应用提供一定高度灵活和成本低的解决办法。 at89c2051提供以下标准功能：2k字节闪速存储器，128字节ram，15根i/o口，两个16位定时器，一个五向量两级中断结构，一个全双工串行口，一个精密模拟比较器以及两种可选 的软件节电工作方式。空闲方停止cpu工作但允许ram、定时器/计数器、串行工作口和中断系统继续工作。掉电方式保存ram内容但振荡器停止工作并禁止有其它部件的工作到下一个硬件复位。 at89c2051设计有2个程序保密位，保密位1被编程之后，程序存储器不能再被编程除非做一次擦除，保密位2被编程之后，程序不能被读出。 at89c2051可以采用下面两种方法开发应用系统。 1、由于89c2051内部程序存贮器为flash，所以修改它内部的程序十分方便快捷，只要配备一个可以编程89c2051的编程器即可。调试人员可以采用程序编辑-编译-固化-插到电路板中试验这样反复循环的方法，对于熟练的mcs-51程序员来说，这种调试方法并不十分困难。但是做这种调试不能够了解片内ram的内容和程序的走向等有关信息。 2、将普通8031/80c31仿真器的仿真插头中p1.0p1.7和p3.0p3.6引出来仿真2051,这种方法可以运用单步、断点的调试方法，但是仿真不够真实，比如，2051的内部模拟比较器功能，p1口、p3口的增强下拉能力等等。 at89c2051芯片引脚图at89c2051的引脚图如右图所示。 1、vcc：电源电压。 2、gnd：地。 3、p1口：p1口是一个8位双向i/o口。口引脚p1.2p1.7提供内部上拉电阻，p1.0和p1.1要求外部上拉电阻。p1.0和p1.1还分别作为片内精密模拟比较器的同相输入(ani0)和反相输入(ain1)。p1口输出缓冲器可吸收20ma电流并能直接驱动led显示。当p1口引脚写入“1”时，其可用作输入端，当引脚p1.2p1.7用作输入并被外部拉低时，它们将因内部的写入“1”