【正文】 ce) with only minimal intervention by the processor. DMA transfers are managed by a third peripheral called a DMA 。一種直接在兩個(gè)外設(shè)（通常是內(nèi)存和I/O設(shè)備）之間進(jìn)行數(shù)據(jù)傳輸?shù)募夹g(shù)，它只要處理器最少的介入。DMA傳輸由叫DMA控制器的第三方外設(shè)進(jìn)行管理?！　RAM（動(dòng)態(tài)隨機(jī)訪問(wèn)存儲(chǔ)器）Dynamic RandomAccess Memory. A type of RAM that maintains its contents only as long as the data stored in the device is refreshed at regular refresh cycles are usually performed by a peripheral called a DRAM 。一種RAM，存儲(chǔ)在其設(shè)備中的數(shù)據(jù)被定期刷新時(shí)才能保存它的內(nèi)容。刷新周期一般由一個(gè)叫DRAM控制器的外設(shè)完成?！　ata bus（數(shù)據(jù)總線）A set of electrical lines connected to the processor and all of the peripherals with which it municates. When the processor wants to read (write) the contents of a memory location or register within a particular peripheral, it sets the address bus pins appropriately and receives (transmits) the contents on the data 。當(dāng)一個(gè)處理器想去寫(xiě)（讀）某一特定外設(shè)中的存儲(chǔ)器地址或寄存器中的內(nèi)容時(shí)，處理器設(shè)置地址總線并在數(shù)據(jù)總線上接收（傳輸）內(nèi)容?！　eadline（死線）The time at which a particular set of putations must be pleted. See alsorealtime 。請(qǐng)看實(shí)時(shí)系統(tǒng)?！　eadlock（死鎖）An unwanted software situation in which an entire set of tasks is blocked, w　　aiting for an event that only a task within the same set can cause. If a deadlock occurs, the only solution is to reset the hardware. However, it is usually possible to prevent deadlocks altogether by following certain software design ，在這個(gè)狀態(tài)下，所有的任務(wù)因?yàn)榈却粋€(gè)只有在這些被阻塞任務(wù)之一才能產(chǎn)生的事件而被阻塞。如果死鎖發(fā)生，唯一解決的方法是重啟動(dòng)硬件。但是，通過(guò)可靠的軟件設(shè)計(jì)實(shí)踐活動(dòng)通?？梢苑乐顾梨i的發(fā)生?！　ebug monitor（除錯(cuò)監(jiān)視程序）A piece of embedded software that has been designed specifically for use as a debugging tool. It usually resides in ROM and municates with a debugger via a serial port or network connection. The debug monitor provides a set of primitive mands to view and modify memory locations and registers, create and remove breakpoints, and execute your program. The debugger bines these primitives to fulfill higherlevel requests like program download and 。它一般被放在ROM中，通過(guò)串口或網(wǎng)絡(luò)與除錯(cuò)器進(jìn)行通訊。除錯(cuò)監(jiān)視程序提供一個(gè)簡(jiǎn)單的命令集來(lái)顯示和內(nèi)存地址和寄存器、建立和移除斷點(diǎn)，并且運(yùn)行你的程序。除錯(cuò)監(jiān)視器組合這些簡(jiǎn)單的命令去實(shí)現(xiàn)象程序下載各單步調(diào)試等高端的請(qǐng)求?！　ebugger（除錯(cuò)器）A software development tool used to test and debug embedded software. The debugger runs on a host puter and connects to the target through a serial port or network connection. Using a debugger you can download software to the target for immediate execution. You can also set breakpoints and examine the contents of specific memory locations and ，被用來(lái)對(duì)嵌入式軟件進(jìn)行測(cè)試和除錯(cuò)。除錯(cuò)器在宿主機(jī)上運(yùn)行并且通過(guò)串口或網(wǎng)絡(luò)連接到目標(biāo)機(jī)上。你能使用除錯(cuò)器下載軟件到目標(biāo)機(jī)并直接運(yùn)行。你也可以設(shè)置斷點(diǎn)并檢查特定內(nèi)存地址或寄存器的內(nèi)容。device driver（設(shè)備驅(qū)動(dòng)程序）A software module that hides the details of a particular peripheral and provides a highlevel programming interface to it. 一個(gè)軟件模塊，它隱藏特定外設(shè)的細(xì)節(jié)并提供高級(jí)的外設(shè)編程接口?！　evice programmer（設(shè)備編程器）A tool for programming nonvolatile memories and other electricallyprogrammable devices. Typically, the programmable device is inserted into a socket on the device programmer and the contents of a memory buffer are then transferred into 。典型地，可編程設(shè)備被插到設(shè)備編程器的接口上，接著內(nèi)存緩存器中的內(nèi)容被傳送到它里面?！　igital signal processor（數(shù)字信號(hào)處理器）A device that is similar to a microprocessor, except that the internal CPU has been optimized for use in applications involving discretetime signal processing. In addition to standard microprocessor instructions, DSPs usually support a set of plex instructions to perform mon signalprocessing 　putations DSP families are TIs 320Cxx and Motorolas 5600x ，不同的是它內(nèi)部的CPU被優(yōu)化，用于特定的應(yīng)用，如離散信號(hào)處理。除了標(biāo)準(zhǔn)的微處理器指令外，DSP常常支持復(fù)雜指令集去非?？斓赝瓿赏ㄓ玫男盘?hào)處理計(jì)算。通用DSP家庭是TI的320Cxx和Motorola的5600x系列?！　EPROM（電可擦的，可編程的只讀存儲(chǔ)器）Electrically Erasable, Programmable ReadOnly Memory. (PronouncedDoubleEPROM.) A type of ROM that can be erased electronically.電可擦的，可編程的只讀存儲(chǔ)器。一種ROM能被電擦除?！　PROM（可擦的，可編程的只讀存儲(chǔ)器）Erasable, Programmable ReadOnly Memory. A type of ROM that can be erased by exposing it to ultraviolet light. Once erased, an EPROM can be reprogrammed with the help of a device 。一次擦除后，EPROM可以在設(shè)備編程器的幫助下被重編程?！　mbedded system（嵌入式系統(tǒng)）A bination of puter hardware and software, and perhaps additional mechanical or other parts, designed to perform a dedicated function. In some cases, embedded systems are part of a larger system or product, as is the case of an antilock braking system in a car. Contrast with generalpurpose ，或許還加上機(jī)械等其他部分，被設(shè)計(jì)來(lái)完成專門的功能。在一些情況下，嵌入式系統(tǒng)是一個(gè)大的系統(tǒng)或產(chǎn)品的一部分，就象汽車上的防抱死裝置。與通用計(jì)算機(jī)相對(duì)。