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llers.&nbsp;<br />
&nbsp;&nbsp;&nbsp;一种介于处理器和外界之间的硬件设备。一般的实例是开关、LED、串口和网络控制&nbsp;<br />
器。&nbsp;<br />
I/O&nbsp;map（I/O映射）&nbsp;<br />
A&nbsp;table&nbsp;or&nbsp;diagram&nbsp;containing&nbsp;the&nbsp;name&nbsp;and&nbsp;address&nbsp;range&nbsp;of&nbsp;each&nbsp;peripheral&nbsp;&nbsp;<br />
addressable&nbsp;by&nbsp;the&nbsp;processor&nbsp;within&nbsp;the&nbsp;I/O&nbsp;space.&nbsp;I/O&nbsp;maps&nbsp;are&nbsp;a&nbsp;helpful&nbsp;ai&nbsp;<br />
d&nbsp;in&nbsp;getting&nbsp;to&nbsp;know&nbsp;the&nbsp;target.&nbsp;<br />
一张包含每个外设的名字和地址的表格或图表，可由处理器在I/O空间中设定地址。I/O&nbsp;<br />
映射对得知目标机情况非常有利。&nbsp;<br />
I/O&nbsp;space（I/O空间）&nbsp;<br />
A&nbsp;special&nbsp;memory&nbsp;region&nbsp;provided&nbsp;by&nbsp;some&nbsp;processors&nbsp;and&nbsp;generally&nbsp;reserved&nbsp;f&nbsp;<br />
or&nbsp;the&nbsp;attachment&nbsp;of&nbsp;I/O&nbsp;devices.&nbsp;Memory&nbsp;locations&nbsp;and&nbsp;registers&nbsp;within&nbsp;an&nbsp;I&nbsp;<br />
/O&nbsp;space&nbsp;can&nbsp;be&nbsp;accessed&nbsp;only&nbsp;via&nbsp;special&nbsp;instructions.&nbsp;For&nbsp;example,&nbsp;process&nbsp;<br />
ors&nbsp;in&nbsp;the&nbsp;80x86&nbsp;family&nbsp;have&nbsp;special&nbsp;I/O&nbsp;space&nbsp;instructions&nbsp;called&nbsp;in&nbsp;and&nbsp;ou&nbsp;<br />
t.&nbsp;Contrast&nbsp;with&nbsp;memory&nbsp;space.&nbsp;<br />
一个由处理器提供的特殊内存区域，一般为为I/O设备的附件保留。在I/O空间的内存位&nbsp;<br />
置和寄存器只能通过特殊的指定进行访问。例如：80X86家族的处理器有叫做in&nbsp;/&nbsp;out的&nbsp;<br />
特殊的I/O空间指令。相对内存空间而言。&nbsp;<br />
ISR（中断服务程序）&nbsp;<br />
See&nbsp;interrupt&nbsp;service&nbsp;routine.&nbsp;<br />
instruction&nbsp;pointer（指令指针）&nbsp;<br />
A&nbsp;register&nbsp;in&nbsp;the&nbsp;processor&nbsp;that&nbsp;contains&nbsp;the&nbsp;address&nbsp;of&nbsp;the&nbsp;next&nbsp;instructio&nbsp;<br />
n&nbsp;to&nbsp;be&nbsp;executed.&nbsp;Also&nbsp;known&nbsp;as&nbsp;a&nbsp;program&nbsp;counter.&nbsp;<br />
包含下一条要执行指令地址的处理器中的寄存器。也叫程序计数器。&nbsp;<br />
Interrupt（中断）&nbsp;<br />
An&nbsp;asynchronous&nbsp;electrical&nbsp;signal&nbsp;from&nbsp;a&nbsp;peripheral&nbsp;to&nbsp;the&nbsp;processor.&nbsp;When&nbsp;t&nbsp;<br />
he&nbsp;peripheral&nbsp;asserts&nbsp;this&nbsp;signal,&nbsp;we&nbsp;say&nbsp;that&nbsp;an&nbsp;interrupt&nbsp;occurs.&nbsp;When&nbsp;an&nbsp;&nbsp;<br />
interrupt&nbsp;occurs,&nbsp;the&nbsp;current&nbsp;state&nbsp;of&nbsp;the&nbsp;processor&nbsp;is&nbsp;saved&nbsp;and&nbsp;an&nbsp;interru&nbsp;<br />
pt&nbsp;service&nbsp;routine&nbsp;is&nbsp;executed.&nbsp;When&nbsp;the&nbsp;interrupt&nbsp;service&nbsp;routine&nbsp;exits,&nbsp;co&nbsp;<br />
ntrol&nbsp;of&nbsp;the&nbsp;processor&nbsp;is&nbsp;returned&nbsp;to&nbsp;whatever&nbsp;part&nbsp;of&nbsp;the&nbsp;software&nbsp;was&nbsp;prev&nbsp;<br />
iously&nbsp;running.&nbsp;<br />
一个从外设到处理器的异步电信号。当外设发出这个信号，我们说一个中断发生。当一&nbsp;<br />
个中断发生，当前的处理器状态被保存并且中断服务程序开始运行。当中断服务程序退&nbsp;<br />
出，对处理器的控制权转到先前运行的那个软件上。&nbsp;<br />
interrupt&nbsp;latency（中断延迟）&nbsp;<br />
The&nbsp;amount&nbsp;of&nbsp;time&nbsp;between&nbsp;the&nbsp;assertion&nbsp;of&nbsp;an&nbsp;interrupt&nbsp;and&nbsp;the&nbsp;start&nbsp;of&nbsp;th&nbsp;<br />
e&nbsp;associated&nbsp;interrupt&nbsp;service&nbsp;routine.&nbsp;<br />
在中断发生和相关的中断服务程序运行之间的时间长短。&nbsp;<br />
interrupt&nbsp;service&nbsp;routine（中断服务程序）&nbsp;<br />
A&nbsp;piece&nbsp;of&nbsp;software&nbsp;executed&nbsp;in&nbsp;response&nbsp;to&nbsp;a&nbsp;particular&nbsp;interrupt.&nbsp;<br />
响应特定中断而运行的一小段软件。&nbsp;<br />
interrupt&nbsp;type（中断类型）&nbsp;<br />
A&nbsp;unique&nbsp;number&nbsp;associated&nbsp;with&nbsp;each&nbsp;interrupt.&nbsp;<br />
和每一个中断相关联的唯一数字。&nbsp;<br />
interrupt&nbsp;vector&nbsp;（中断向量）&nbsp;<br />
The&nbsp;address&nbsp;of&nbsp;an&nbsp;interrupt&nbsp;service&nbsp;routine.&nbsp;<br />
中断服务程序所在的地址。&nbsp;<br />
interrupt&nbsp;vector&nbsp;table（中断向量表）&nbsp;<br />
A&nbsp;table&nbsp;containing&nbsp;interrupt&nbsp;vectors&nbsp;and&nbsp;indexed&nbsp;by&nbsp;interrupt&nbsp;type.&nbsp;This&nbsp;tab&nbsp;<br />
le&nbsp;contains&nbsp;the&nbsp;processor&quot;s&nbsp;mapping&nbsp;between&nbsp;interrupts&nbsp;and&nbsp;interrupt&nbsp;service&nbsp;<br />
&nbsp;routines&nbsp;and&nbsp;must&nbsp;be&nbsp;initialized&nbsp;by&nbsp;the&nbsp;programmer.&nbsp;<br />
一个表格，包含由中断类型决定的中断向量和索引。这个表格包含中断与中断服务程序&nbsp;<br />
之间的处理器的映射，必须由程序员进行初始化。&nbsp;<br />
intertask&nbsp;communication（进程间通讯）&nbsp;<br />
A&nbsp;mechanism&nbsp;used&nbsp;by&nbsp;tasks&nbsp;and&nbsp;interrupt&nbsp;service&nbsp;routines&nbsp;to&nbsp;share&nbsp;informatio&nbsp;<br />
n&nbsp;and&nbsp;synchronize&nbsp;their&nbsp;access&nbsp;to&nbsp;shared&nbsp;resources.&nbsp;The&nbsp;most&nbsp;common&nbsp;building&nbsp;<br />
&nbsp;blocks&nbsp;of&nbsp;intertask&nbsp;communication&nbsp;are&nbsp;semaphores&nbsp;and&nbsp;mutexes.&nbsp;<br />
一种被用来在任务和中断服务程序之间共享信息和同步它们对共享资源访问的机制。大&nbsp;<br />
部分进程间通讯的建立的基石是信号灯和互斥。&nbsp;<br />
K&nbsp;<br />
Kernel（内核）&nbsp;<br />
An&nbsp;essential&nbsp;part&nbsp;of&nbsp;any&nbsp;multitasking&nbsp;operating&nbsp;system,&nbsp;the&nbsp;kernel&nbsp;contains&nbsp;&nbsp;<br />
just&nbsp;the&nbsp;scheduler&nbsp;and&nbsp;context-switch&nbsp;routine.&nbsp;<br />
任何多任务操作系统的本质部分，内核仅仅包含调度程序和上下文切换进程。&nbsp;<br />
L&nbsp;<br />
Linker（连接程序）&nbsp;<br />
A&nbsp;software&nbsp;development&nbsp;tool&nbsp;that&nbsp;accepts&nbsp;one&nbsp;or&nbsp;more&nbsp;object&nbsp;files&nbsp;as&nbsp;input&nbsp;a&nbsp;<br />
nd&nbsp;outputs&nbsp;a&nbsp;relocatable&nbsp;program.&nbsp;The&nbsp;linker&nbsp;is&nbsp;thus&nbsp;run&nbsp;after&nbsp;all&nbsp;of&nbsp;the&nbsp;so&nbsp;<br />
urce&nbsp;files&nbsp;have&nbsp;been&nbsp;compiled&nbsp;or&nbsp;assembled.&nbsp;<br />
一种能把一个或更多目标文件组合成可输入和输出的可重定位程序的开发工具。连接程&nbsp;<br />
序在所有的源文件都被编译或汇编之后运行。&nbsp;<br />
Locator（定位程序）&nbsp;<br />
A&nbsp;software&nbsp;development&nbsp;tool&nbsp;that&nbsp;assigns&nbsp;physical&nbsp;addresses&nbsp;to&nbsp;the&nbsp;relocatab&nbsp;<br />
le&nbsp;program&nbsp;produced&nbsp;by&nbsp;the&nbsp;linker.&nbsp;This&nbsp;is&nbsp;the&nbsp;last&nbsp;step&nbsp;in&nbsp;the&nbsp;preparation&nbsp;&nbsp;<br />
of&nbsp;software&nbsp;for&nbsp;execution&nbsp;by&nbsp;an&nbsp;embedded&nbsp;system&nbsp;and&nbsp;the&nbsp;resulting&nbsp;file&nbsp;is&nbsp;ca&nbsp;<br />
lled&nbsp;an&nbsp;executable.&nbsp;In&nbsp;some&nbsp;cases,&nbsp;the&nbsp;locator&quot;s&nbsp;function&nbsp;may&nbsp;be&nbsp;hidden&nbsp;with&nbsp;<br />
in&nbsp;the&nbsp;linker.&nbsp;<br />
一种分配物理地址给连接程序处理过的可重定位程序的软件开发工具。这是准备一个软&nbsp;<br />
件在嵌入式系统中运行的最后一步，并且结果文件叫做可执行的。在一些情况下，定位&nbsp;<br />
程序功能隐藏在连接程序中。&nbsp;<br />
logic&nbsp;analyzer（逻辑分析仪）&nbsp;<br />
A&nbsp;hardware&nbsp;debugging&nbsp;tool&nbsp;that&nbsp;can&nbsp;be&nbsp;used&nbsp;to&nbsp;capture&nbsp;the&nbsp;logic&nbsp;levels&nbsp;(0&nbsp;or&nbsp;<br />
&nbsp;1)&nbsp;of&nbsp;dozens,&nbsp;or&nbsp;even&nbsp;hundreds,&nbsp;of&nbsp;electrical&nbsp;signals&nbsp;in&nbsp;real-time.&nbsp;Logic&nbsp;a&nbsp;<br />
nalyzers&nbsp;can&nbsp;be&nbsp;quite&nbsp;helpful&nbsp;for&nbsp;debugging&nbsp;hardware&nbsp;problems&nbsp;and&nbsp;complex&nbsp;pr&nbsp;<br />
ocessor-peripheral&nbsp;interactions.&nbsp;<br />
一种硬件调试工具，能捕获实时电信号的许多逻辑电平（0或1），逻辑分析仪在调试硬&nbsp;<br />
件问题和复杂的处理外设交互时相当有用。&nbsp;<br />
M&nbsp;<br />
memory&nbsp;map（内存映射）&nbsp;<br />
A&nbsp;table&nbsp;or&nbsp;diagram&nbsp;containing&nbsp;the&nbsp;name&nbsp;and&nbsp;address&nbsp;range&nbsp;of&nbsp;each&nbsp;peripheral&nbsp;&nbsp;<br />
addressable&nbsp;by&nbsp;the&nbsp;processor&nbsp;within&nbsp;the&nbsp;memory&nbsp;space.&nbsp;Memory&nbsp;maps&nbsp;are&nbsp;a&nbsp;help&nbsp;<br />
ful&nbsp;aid&nbsp;in&nbsp;getting&nbsp;to&nbsp;know&nbsp;the&nbsp;target.&nbsp;<br />
一个在内存空间中的，包含每个外设的名字和可由处理器设置的地址范围的表格或图表&nbsp;<br />
。内存映射有助于了解目标机情况。&nbsp;<br />
memory-mapped&nbsp;&nbsp;I/O（内存映射I/O）&nbsp;<br />
An&nbsp;increasingly&nbsp;common&nbsp;hardware&nbsp;design&nbsp;methodology&nbsp;in&nbsp;which&nbsp;I/O&nbsp;devices&nbsp;are&nbsp;&nbsp;<br />
placed&nbsp;into&nbsp;the&nbsp;memory&nbsp;space&nbsp;rather&nbsp;than&nbsp;the&nbsp;I/O&nbsp;space.&nbsp;From&nbsp;the&nbsp;processor&quot;s&nbsp;<br />
&nbsp;point&nbsp;of&nbsp;view,&nbsp;memory-mapped&nbsp;I/O&nbsp;devices&nbsp;look&nbsp;very&nbsp;much&nbsp;like&nbsp;memory&nbsp;devices&nbsp;<br />
.&nbsp;<br />
一种日益流行的硬件设计方法，在这种方法中，I/O设备被放置在内存空间而不是I/O空&nbsp;<br />
间。从处理器的观点看，内存映射I/O设备看上去很象内存一样。&nbsp;<br />
memory&nbsp;space（内存空间）&nbsp;<br />
A&nbsp;processor&quot;s&nbsp;standard&nbsp;address&nbsp;space.&nbsp;Contrast&nbsp;with&nbsp;I/O&nbsp;space.&nbsp;<br />
一个处理器的标准地址空间。相对I/O空间。&nbsp;<br />
Microcontroller（微控制器）&nbsp;<br />
A&nbsp;microcontroller&nbsp;is&nbsp;very&nbsp;similar&nbsp;to&nbsp;a&nbsp;microprocessor.&nbsp;The&nbsp;main&nbsp;difference&nbsp;i&nbsp;<br />
s&nbsp;that&nbsp;a&nbsp;microcontroller&nbsp;is&nbsp;designed&nbsp;specifically&nbsp;for&nbsp;use&nbsp;in&nbsp;embedded&nbsp;system&nbsp;<br />
s&nbsp;Microcontrollers&nbsp;typically&nbsp;include&nbsp;a&nbsp;CPU,&nbsp;memory&nbsp;(a&nbsp;small&nbsp;amount&nbsp;of&nbsp;RAM&nbsp;an&nbsp;<br />
d/or&nbsp;ROM),&nbsp;and&nbsp;other&nbsp;peripherals&nbsp;on&nbsp;the&nbsp;same&nbsp;chip.&nbsp;Common&nbsp;examples&nbsp;are&nbsp;the&nbsp;8&nbsp;<br />
051,&nbsp;Intel&quot;s&nbsp;80196,&nbsp;and&nbsp;Motorola&quot;s&nbsp;68HCxx&nbsp;series.&nbsp;<br />
微控制器很像微处理器。主要的差别在于微控制器被特殊设计用在嵌入式系统中。微控&nbsp;<br />
制器典型地包括CPU、内存（很小的RAM或ROM），还有其他的外设，它们在同一块芯片上&nbsp;<br />
。常见的例子是：8051、Intel80196、Motorola68HCxx系列。&nbsp;<br />
Microprocessor（微处理器）&nbsp;<br />
A&nbsp;piece&nbsp;of&nbsp;silicon&nbsp;containing&nbsp;a&nbsp;general-purpose&nbsp;CPU.&nbsp;The&nbsp;most&nbsp;common&nbsp;example&nbsp;<br />
s&nbsp;are&nbsp;Intel&quot;s&nbsp;80x86&nbsp;and&nbsp;Motorola&quot;s&nbsp;680x0&nbsp;families.&nbsp;<br />
一片包含通用CPU的硅片。常见的例子是：Intel80x86、Motorola&nbsp;680x0系列。&nbsp;<br />
Monitor（监视器）&nbsp;<br />
In&nbsp;the&nbsp;context&nbsp;of&nbsp;this&nbsp;book,&nbsp;a&nbsp;debug&nbsp;monitor.&nbsp;However,&nbsp;there&nbsp;is&nbsp;a&nbsp;second&nbsp;mea&nbsp;<br />
ning&nbsp;for&nbsp;this&nbsp;word&nbsp;that&nbsp;is&nbsp;associated&nbsp;with&nbsp;intertask&nbsp;communication.&nbsp;In&nbsp;that&nbsp;&nbsp;<br />
context,&nbsp;a&nbsp;monitor&nbsp;is&nbsp;a&nbsp;language-level&nbsp;synchronization&nbsp;feature.&nbsp;<br />
在这本书的上下文中，是指调试监视器。然而，第二个意思与任务间通讯相关联。在那&nbsp;<br />
个上下文中，监视器是高级同步机制的特性。&nbsp;<br />
Multiprocessing（多处理）&nbsp;<br />
The&nbsp;use&nbsp;of&nbsp;more&nbsp;than&nbsp;one&nbsp;processor&nbsp;in&nbsp;a&nbsp;single&nbsp;computer&nbsp;system.&nbsp;So-called&nbsp;&quot;m&nbsp;<br />
ultiprocessor&nbsp;systems&quot;&nbsp;usually&nbsp;have&nbsp;a&nbsp;common&nbsp;memory&nbsp;space&nbsp;through&nbsp;which&nbsp;the&nbsp;&nbsp;<br />
processors&nbsp;can&nbsp;communicate&nbsp;and&nbsp;share&nbsp;data.&nbsp;In&nbsp;addition,&nbsp;some&nbsp;multiprocessor&nbsp;&nbsp;<br />
systems&nbsp;support&nbsp;parallel&nbsp;processing.&nbsp;<br />
在单个的计算机系统中有多个处理器。被叫作“多处理器系统”的一般有公用的内存空&nbsp;<br />
间，处理器通过它们进行通讯和共享数据。另外，一些多处理器系统支持并行处理。&nbsp;<br />
Multitasking&nbsp;（多任务）&nbsp;<br />
The&nbsp;execution&nbsp;of&nbsp;multiple&nbsp;software&nbsp;routines&nbsp;in&nbsp;pseudo-parallel.&nbsp;Each&nbsp;routine&nbsp;<br />
&nbsp;represents&nbsp;a&nbsp;separate&nbsp;&quot;thread&nbsp;of&nbsp;execution&quot;&nbsp;and&nbsp;is&nbsp;referred&nbsp;to&nbsp;as&nbsp;a&nbsp;task.&nbsp;T&nbsp;<br />
he&nbsp;operating&nbsp;system&nbsp;is&nbsp;responsible&nbsp;for&nbsp;simulating&nbsp;parallelism&nbsp;by&nbsp;parceling&nbsp;o&nbsp;<br />
ut&nbsp;the&nbsp;processor&quot;s&nbsp;time.&nbsp;<br />
伪并行运行的多个软件程序。每一个程序表现得像分开的“执行的线程”并且被看作是&nbsp;<br />
一个任务。操作系统通过分配处理器时间来模拟并行方式。&nbsp;<br />
Mutex（互斥）&nbsp;<br />
A&nbsp;data&nbsp;structure&nbsp;for&nbsp;mutual&nbsp;exclusion,&nbsp;also&nbsp;known&nbsp;as&nbsp;a&nbsp;binary&nbsp;semaphore.&nbsp;A&nbsp;m&nbsp;<br />
utex&nbsp;is&nbsp;basically&nbsp;just&nbsp;a&nbsp;multitasking-aware&nbsp;binary&nbsp;flag&nbsp;that&nbsp;can&nbsp;be&nbsp;used&nbsp;to&nbsp;&nbsp;<br />
synchronize&nbsp;the&nbsp;activities&nbsp;of&nbsp;multiple&nbsp;tasks.&nbsp;As&nbsp;such,&nbsp;it&nbsp;can&nbsp;be&nbsp;used&nbsp;to&nbsp;pro&nbsp;<br />
tect&nbsp;critical&nbsp;sections&nbsp;of&nbsp;the&nbsp;code&nbsp;from&nbsp;interruption&nbsp;and&nbsp;shared&nbsp;resources&nbsp;fr&nbsp;<br />
om&nbsp;simultaneous&nbsp;use.&nbsp;<br />
表现互斥现象的数据结构，也被当作二元信号灯。一个互斥基本上是一个多任务敏感的&nbsp;<br />
二元信号，它能用作同步多任务的行为，它常用作保护从中断来的临界段代码并且在共&nbsp;<br />