【正文】 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。一種ROM能被電擦除?！　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。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。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。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?！　eadline（死線）The time at which a particular set of putations must be pleted. See alsorealtime 。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。D　　DMA（直接內(nèi)存訪問(wèn)）　　Direct Memory Access. A technique for transferring data directly between two peripherals (usually memory and an I/O device) with only minimal intervention by the processor. DMA transfers are managed by a third peripheral called a DMA ?！　ritical section（臨界段）A block of code that must be executed in sequence and without interruption to guarantee correct operation of the software. See also race ，并且不能被中斷，否則不能保證軟件正確地操作。做這個(gè)工作的一段代碼必須具有處理器特權(quán)?！　ompiler（編譯器）A software development tool that translates highlevel language programs into the machinelanguage instructions that a particular processor can understand and 。Intel的80x86家族是是典型的CISC處理器。大多數(shù)除錯(cuò)工具提供增加與刪除一個(gè)斷點(diǎn)的機(jī)制。樣例源程序必須能在需要時(shí)被修改、編譯并與軟件包的剩下的部分連接起來(lái)。　binary semaphore(二元信號(hào))　A type of semaphore with just two states. Also called a 。　　assembly language（匯編語(yǔ)言）A humanreadable form of a processors instruction set. Most processorspecific functions must be written in assembly 。如果地址總線有n條電子線路，處理器能唯一尋址高達(dá)2^n的地址空間。ASIC（專用集成電路）：ApplicationSpecific Integrated Circuit. A piece of customdesigned hardware in a 。 System Level IC. Register Transfer Level. Hardware Description Language. Electronic Design Automation. 電子設(shè)計(jì)自動(dòng)化 FPGA: Field Programmable Gate Array. 現(xiàn)場(chǎng)可編程 門(mén)陣列 GAL: 硬件描述語(yǔ)言 IP: 智能模塊 PAL: 寄存器傳輸級(jí)描述） SOC: 一個(gè)在一個(gè)芯片上定制設(shè)計(jì)的硬件?！　pplication software（應(yīng)用軟件）Describes software modules specific to a particular embedded project. The application software is unlikely to be reusable across embedded platforms, simply because each embedded system has a different 。大多數(shù)處理器相關(guān)的功能必須用匯編語(yǔ)言編寫(xiě)。也叫互斥信號(hào)?！　ondout processor （外合處理器）A special version of a processor that has some of the internal signals brought out to external pins. A bondout processor is most often found within an 　emulator and is never intended to be used in a production system. 一種特殊版本的處理器，它有一些，內(nèi)部的信號(hào)能傳達(dá)到外置的針腳上。2　　CISC（復(fù)雜指令集計(jì)算機(jī)）Complex Instruction Set Computer. Describes the architecture of a processor family. CISC processors generally feature variablelength instructions, multiple addressing formats, and contain only a small number of generalpurpose 　　registers. Intels 80x86 family is the quintessential example of CISC. Contrast with 。相對(duì)于RISC而言。　　context （上下文）The current state of the processors registers and ?！　ounting semaphore（計(jì)數(shù)信號(hào)）　A type of semaphore that is used to track multiple resources of the same type. An attempt to take a counting semaphore is blocked only if all of the available resources are in use. Contrast with binary 。參照：競(jìng)爭(zhēng)狀況。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。刷新周期一般由一個(gè)叫DRAM控制器的外設(shè)完成。請(qǐng)看實(shí)時(shí)系統(tǒng)?！　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 。　　Debugger（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)。device driver（設(shè)備驅(qū)動(dòng)程序）A software module t