單片機(jī)外文翻譯--修改版

Electric boiler temperature system 1.MCU A microcontroller (or MCU) is a computer-on-a-chip. It is a type of microprocessor emphasizing self-sufficiency and cost-effectiveness, in contrast to a general-purpose microprocessor (the kind used in a PC). The majority of computer systems in use today are embedded in other machinery, such as telephones, clocks, appliances, vehicles, and infrastructure. An embedded system usually has minimal requirements for memory and program length and may require simple but unusual input/output systems. For example, most embedded systems lack keyboards, screens, disks, printers, or other recognizable I/O devices of a personal computer. They may control electric motors, relays or voltages, and read switches, variable resistors or other electronic devices. Often, the only I/O device readable by a human is a single light-emitting diode, and severe cost or power constraints can even eliminate that. In contrast to general-purpose CPUs, microcontrollers do not have an address bus or a data bus, because they integrate all the RAM and non-volatile memory on the same chip as the CPU. Because they need fewer pins, the chip can be placed in a much smaller, cheaper package. Integrating the memory and other peripherals on a single chip and testing them as a unit increases the cost of that chip, but often results in decreased net cost of the embedded system as a whole. (Even if the cost of a CPU that has integrated peripherals is slightly more than the cost of a CPU + external peripherals, having fewer chips typically allows a smaller and cheaper circuit board, and reduces the labor required to assemble and test the circuit board). This trend leads to design. A microcontroller is a single integrated circuit, commonly with the following features: central processing unit - ranging from small and simple 4-bit processors to sophisticated 32- or 64-bit processors input/output interfaces such as serial ports (UARTs) other serial communications interfaces like IC, Serial Peripheral Interface and Controller Area Network for system interconnect peripherals such as timers and watchdog RAM for data storage ROM, EPROM, EEPROM or Flash memory for program storage clock generator - often an oscillator for a quartz timing crystal, resonator or RC circuit many include analog-to-digital converters . This integration drastically reduces the number of chips and the amount of wiring and PCB space that would be needed to produce equivalent systems using separate chips and have proved to be highly popular in embedded systems since their introduction in the 1970s. Some microcontrollers can afford to use a Harvard architecture: separate memory buses for instructions and data, allowing accesses to take place concurrently. The decision of which peripheral to integrate is often difficult. The Microcontroller vendors often trade operating frequencies and system design flexibility against time-to-market requirements from their customers and overall lower system cost. Manufacturers have to balance the need to minimize the chip size against additional functionality. Microcontroller architectures are available from many different vendors in so many varieties that each instruction set architecture could rightly belong to a category of their own. Chief among these are the 8051, Z80 and ARM derivatives.citation needed A microcontroller (also MCU or C) is a functional computer system-on-a-chip. It contains a processor core, memory, and programmable input/output peripherals. Microcontrollers include an integrated CPU, memory (a small amount of RAM, program memory, or both) and peripherals capable of input and output. It emphasizes high integration, in contrast to a microprocessor which only contains a CPU (the kind used in a PC). In addition to the usual arithmetic and logic elements of a general purpose microprocessor, the microcontroller integrates additional elements such as read-write memory for data storage, read-only memory for program storage, Flash memory for permanent data storage, peripherals, and input/output interfaces. At clock speeds of as little as 32KHz, microcontrollers often operate at very low speed compared to microprocessors, but this is adequate for typical applications. They consume relatively little power (milliwatts or even microwatts), and will generally have the ability to retain functionality while waiting for an event such as a button press or interrupt. Power consumption while sleeping (CPU clock and peripherals disabled) may be just nanowatts, making them ideal for low power and long lasting battery applications. Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, remote controls, office machines, appliances, power tools, and toys. By reducing the size, cost, and power consumption compared to a design using a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to electronically control many more processes. The majority of computer systems in use today are embedded in other machinery, such as automobiles, telephones, appliances, and peripherals for computer systems. These are called embedded systems. While some embedded systems are very sophisticated, many have minimal requirements for memory and program length, with no operating system, and low software complexity. Typical input and output devices include switches, relays, solenoids, LEDs, small or custom LCD displays, radio frequency devices, and sensors for data such as temperature, humidity, light level etc. Embedded systems usually have no keyboard, screen, disks, printers, or other recognizable I/O devices of a personal computer, and may lack human interaction devices of any kind. It is mandatory that microcontrollers provide real time response to events in the embedded system they are controlling. When certain events occur, an interrupt system can signal the processor to suspend processing the current instruction sequence and to begin an interrupt service routine (ISR). The ISR will perform any processing required based on the source of the interrupt before returning to the original instruction sequence. Possible interrupt sources are device dependent, and often include events such as an internal timer overflow, completing an analog to digital conversion, a logic level change on an input such as from a button being pressed, and data received on a communication link. Where power consumption is important as in battery operated devices, interrupts may also wake a microcontroller from a low power sleep state where the processor is halted until required to do something by a peripheral event. Microcontroller programs must fit in the available on-chip program memory, since it would be costly to provide a system with external, expandable, memory. Compilers and assembly language are used to turn high-level language programs into a compact machine code for storage in the microcontrollers memory. Depending on the device, the program memory may be permanent, read-only memory that can only be programmed at the factory, or program memory may be field-alterable flash or erasable read-only memory. Since embedded processors are usually used to control devices, they sometimes need to accept input from the device they are controlling. This is the purpose of the analog to digital converter. Since processors are built to interpret and process digital data, i.e. 1s and 0s, they wont be able to do anything with the analog signals that may be being sent to it by a device. So the analog to digital converter is used to convert the incoming data into a form that the processor can recognize. There is also a digital to analog converter that allows the processor to send data to the device it is controlling. In addition to the converters, many embedded microprocessors include a variety of timers as well. One of the most common types of timers is the Programmable Interval Timer, or PIT for short. A PIT just counts down from some value to zero. Once it reaches zero, it sends an interrupt to the processor indicating that it has finished counting. This is useful for devices such as thermostats, which periodically test the temperature around them to see if they need to turn the air conditioner on, the heater on, etc. Time Processing Unit or TPU for short. Is essentially just another timer, but more sophisticated. In addition to counting down, the TPU can detect input events, generate output events, and other useful operations. Dedicated Pulse Width Modulation (PWM) block makes it possible for the CPU to control power converters, resistive loads, motors, etc., without using lots of CPU resources in tight timer loops. Universal Asynchronous Receiver/Transmitter (UART) block makes it possible to receive and transmit data over a serial line with very little load on the CPU. For those wanting ethernet one can use an external chip like Crystal Semiconductor CS8900A, Realtek RTL8019, or Microchip ENC 28J60. All of them allow easy interfacing with low pin count. 中文翻譯： 1.單片機(jī) 單片機(jī)即單片微型計(jì)算機(jī)，是把中央處理器、存儲(chǔ)器、定時(shí) /計(jì)數(shù)器、輸入輸出接口都集成在一塊集成電路芯片上的微型計(jì)算機(jī)。與應(yīng)用在個(gè)人電腦中的通用型微處理器相比，它更強(qiáng)調(diào)自供應(yīng)（不用外接硬件）和節(jié)約成本。它的最大優(yōu)點(diǎn)是體積小，可放在儀表內(nèi)部，但存儲(chǔ)量小，輸入輸出接口簡單，功能較低。由于其發(fā)展非常迅速，舊的單片機(jī)的定義已不能滿足，所以在很多應(yīng)用場合被稱為范圍更廣的微控制器，但是目前在中國大陸仍多沿用 “ 單片機(jī) ” 的稱呼。 絕大多數(shù)現(xiàn)在的單片機(jī)都是基于馮 諾伊曼結(jié)構(gòu)的，這種結(jié)構(gòu)清楚地定義了嵌入式系 統(tǒng)所必需的四個(gè)基本部分：一個(gè)中央處理器核心，程序存儲(chǔ)器（只讀存儲(chǔ)器或者閃存）、數(shù)據(jù)存儲(chǔ)器（隨機(jī)存儲(chǔ)器），一個(gè)或者更多的定時(shí) /計(jì)時(shí)器，還有用來與外圍設(shè)備以及擴(kuò)展資源進(jìn)行通信的輸入 /輸出端口 所有這些都被集成在單個(gè)集成電路芯片上。說單片機(jī)與通用型中央處理單元芯片不同是因?yàn)榍罢咭话愫苋菀着浜献钚⌒偷耐獠恐С中酒瞥晒ぷ饔?jì)算機(jī)。這樣就可以很容易的把單片機(jī)系統(tǒng)植入裝置內(nèi)部來控制裝置了。近年來為了在指令和數(shù)據(jù)上使用不同的字寬，并提高處理器流水線速度，哈佛結(jié)構(gòu)在微控制器和 DSP 也逐漸得到了廣泛的應(yīng)用。 傳統(tǒng)的微處理器 是不允許這么做的。它要完成單片機(jī)的工作，就必須連接一些其他芯片。比如說，片上沒有數(shù)據(jù)存儲(chǔ)器，就必須要添加一些 RAM 的存儲(chǔ)芯片，雖然所添加存儲(chǔ)器的容量很靈活，但是至少還是要添加，另外還需要添加很多連線來傳遞芯片之間的數(shù)據(jù)。 比如，一個(gè)典型的微控制器只需要一個(gè)時(shí)鐘發(fā)生器和很少的 RAM 和 ROM(或者 EPROM, E2PROM)就可以在軟件和晶振下工作了。同時(shí)，微控制器具有豐富的輸入輸出設(shè)備，像是模擬數(shù)字轉(zhuǎn)換 (ADC)，定時(shí)器，串口或者其他串行通訊接口 (比如 I2C，串行外圍接口 (SPI),控制器局域網(wǎng) )。通常，這些 繼承在內(nèi)部的設(shè)備可以通過特殊的指令來操作。 一些現(xiàn)代的微控制器支持一些內(nèi)建的高級(jí)編程語言，比如 BASIC 語言。 一個(gè)微控制器（也 叫 MCU）是一個(gè) 微型 計(jì)算 芯 片。它包含一個(gè)處理器 、一個(gè) 內(nèi)存（有少量的 RAM ，程序存儲(chǔ)器，或兩者兼而有之）和 一個(gè) 可編程輸入 /輸出外設(shè)。 它強(qiáng)調(diào) 高度集成 ，而相比之下，一個(gè)微處理器只包含一個(gè) CPU （ 比如 一臺(tái)PC ） 。除了通常的算術(shù)和邏輯要素 等 一般用途的微處理器，微控制器 還 集成了更多的要素，如讀寫存儲(chǔ)器的數(shù)據(jù)存儲(chǔ)，只讀存儲(chǔ)器 的 存儲(chǔ)程序，快閃記憶體的永久數(shù)據(jù)存儲(chǔ)，外設(shè)，和輸入 /輸出接口。 在時(shí)鐘頻率只有 32Mhz 的情況下 ，微操作 系統(tǒng) 往往以非常低的速度相 運(yùn)行 ，但是這足 夠典型的應(yīng)用 。他們消耗較少的功率（毫瓦或什微） ， 且具有 保持功能，同時(shí) 可以 等待一個(gè)事件，如一個(gè)按鈕的 按下或中斷。 在睡眠狀態(tài) 時(shí) ， CPU 時(shí)鐘和外設(shè)禁用，從而使它們適合用于低功耗和長期持久的電池應(yīng)用。 微控制器 廣泛應(yīng) 用于自動(dòng)控制產(chǎn)品和設(shè)備，如汽車發(fā)動(dòng)機(jī)控制系統(tǒng)，遠(yuǎn)程控制 系統(tǒng) ，辦公室機(jī)器 設(shè)備系統(tǒng) ，家用電器，電動(dòng)工具，和玩具 等 。通過降低尺寸，成本和能耗，設(shè)計(jì)使用單獨(dú)的微處理器，內(nèi)存和輸入 /輸出設(shè)備，