【单选题】
8×51的P0采用哪种电路结构?___
A. 集电极开路式输出
B. 基极开路式输出
C. 发射机开路式输出
D. 图腾柱输出
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答案
B
解析
暂无解析
相关试题
【单选题】
17在8×51里,若要扩展外部存储器时,数据总线连接哪个输入/输出端口?___
A. P0
B. P1
C. P2
D. P3
【单选题】
点亮一般的LED所耗用的电流约为多少?___
A. 1~5µA
B. 10~20µA
C. 1~5mA
D. 10~20mA
【单选题】
19一般地,蜂鸣器属于哪种负载?___
A. 电阻性负载
B. 电感性负载
C. 电容性负载
D. 不导电负载
【单选题】
7405/7406的输出采用哪种电路结构?___
A. 集电极开路式输出
B. 基极开路式输出
C. 发射机开路式输出
D. 图腾柱输出
【单选题】
21在继电器中,NO接点是一种什么接点?___
A. 不使用接点
B. 不存在接点
C. 激磁后即开路的接点
D. 常开接点
【单选题】
22所谓2P的继电器,代表什么意思?___
A. 只有2个接点
B. 两相的负载
C. 两组电源
D. 2组c接点
【单选题】
23共阳极七段数码管显示器的驱动信号有何特色?___
A. 低电平点亮
B. 低电平不亮
C. 高电平点亮
D. 以上皆非
【单选题】
24在8×51的程序里,若要将某个输入/输出端口设置成输入功能,应如何处理?___
A. 先输出高电平到该输入/输出端口
B. 先输出低电平到该输入/输出端口
C. 先读取该输入/输出端口的状态
D. 先保存该输入/输出端口的状态
【单选题】
8×51提供几个外部中断和定时器/计数器中断?___
A. 2,2
B. 3,6
C. 2,3
D. 3,7
【单选题】
8×51的IP缓存器的功能如何?___
A. 设置中断优先级
B. 启动中断功能
C. 设置中断触发信号
D. 定义CPU的网址
【单选题】
28若要让采用低电平触发,则应如何设置?___
A. EX0=0
B. EX0=1
C. IT0=0
D. IT0=1
【单选题】
29在Keil µVision3里进行调试/仿真时,在哪里操作才能触动程序中断?___
A. 在Interrupt System
B. 在Cotorl Box对话框里
C. 直接单击魔术棒按钮即可
D. 直接按0键
【单选题】
30在8×51所提供的中断功能里,下列哪个优先级比较高?___
A. T1
B. RI/TI
C. T0
D. INT0
【单选题】
31在TCON缓存里,IE1的功能是什么?___
A. 触发 IE1中断
B. 指示IE1中断的标志
C. 提高IE1优先等级
D. 取消IE1中断
【单选题】
32在Keil C里,中断子程序与函数又何不同?___
A. 中断子程序不必声明
B. 函数不必声明
C. 中断子程序必须有形式参数
D. 中断子程序一定会有返回值
【单选题】
33若要同时启用INT0及INT1中断功能,则应如何设置?___
A. TCON=0×81
B. IE=0×85
C. IP=0×83
D. IE=0×03
【单选题】
35在8×51的Timer里,若使用Mode 0,其最大计数值为多少个机器周期?___
A. 65636
B. 8192
C. 1024
D. 256
【单选题】
36在12MHz的8×51系统里,哪一种方式一次可定时5ms?___
A. Mode 0及Mode 1
B. Mode 1及Mode 2
C. Mode 2及Mode 3
D. Mode3及Mode 1
【单选题】
37若要让Timer作为外部计数只用,应如何设置?___
A. Gate=0
B. Gate=1
C. C/=0
D. C/=1
【单选题】
39下列哪个不是8×51所提供的省电方式?___
A. PD方式
B. IDL方式
C. LP方式
D. 待机方式
【单选题】
89S51的看门狗有何作用?___
A. 重复执行程序
B. 找回遗失数据
C. 复位系统
D. 防止中毒
【单选题】
41若要启用WDT,则应依次填入WDTRST寄存器哪些数据?___
A. 0xe1、0xe2
B. 0xe1、0x1e
C. 0x1e、0xe1
D. 0x10、0x01
【单选题】
8×51的定时器,在下列哪种方式下具有自动加载功能?___
A. Mode0
B. Mode1
C. Mode2
D. Mode3
【单选题】
45下列哪种AD转换器的转换速度比较快?___
A. 双斜率型AD转换器
B. 比较型AD转换器
C. 连续计数式AD转换器
D. 逐渐接近式AD转换器
【单选题】
46下列哪种AD转换器的精密度比较高?___
A. 双斜率型AD转换器
B. 比较型AD转换器
C. 连续计数式AD转换器
D. 逐步逼近式AD转换器
【单选题】
47对于8×8 LED点阵而言,其中的LED个数及引脚各为多少?___
A. 64、16
B. 16、16
C. 64、12
D. 32、12
【单选题】
48在共阳极型8×8 LED点阵里,其阳极如何连接?___
A. 各行阳极连接到行引脚
B. 各列阳极连接到列引脚
C. 各行阳极连接到列引脚
D. 各列阳极连接到行引脚
【单选题】
49在共阳极型8×8 LED点阵里,其阴极如何连接?___
A. 各行阴极连接到行引脚
B. 各列阴极连接到列引脚
C. 各行阴极连接到列引脚
D. 各列阴极连接到行引脚
【单选题】
50双色8×8 LED点阵的列引脚与行引脚各位多少?___
A. 12、12
B. 8、16
C. 16、8
D. 24、8
【单选题】
___的方向规定由高电位点指向低电位点。
A. 电压
B. 电流
C. 能量
D. 电能
【单选题】
三相电动势到达最大的顺序是不同的,这种达到最大值的先后次序,称三相电源的相序,相序为U-V-W-U,称为___。
A. 正序
B. 负序
C. 逆序
D. 相序
【单选题】
电路的作用是实现能量的传输和转换、信号的___和处理。
A. 连接
B. 传输
C. 控制
D. 传递
【单选题】
电阻器反映导体对电流起阻碍作用的大小,简称___。
A. 电动势
B. 功率
C. 电阻率
D. 电阻
【单选题】
___反映了在不含电源的一段电路中,电流与这段电路两端的电压及电阻的关系。
A. 欧姆定律
B. 楞次定律
C. 部分电路欧姆定律
D. 全欧姆定律
【单选题】
并联电路中的总电流等于各电阻中的___。
A. 倒数之和
B. 相等
C. 电流之和
D. 分配的电流与各电阻值成正比
【单选题】
串联电路中流过每个电阻的电流都___。
A. 电流之和
B. 相等
C. 等于各电阻流过的电流之和
D. 分配的电流与各电阻值成正比
【单选题】
___的一端连在电路中的一点,另一端也同时连在另一点,使每个电阻两端都承受相同的电压,这种联结方式叫电阻的并联。
A. 两个相同电阻
B. 一大一小电阻
C. 几个相同大小的电阻
D. 几个电阻
【单选题】
___的电阻首尾依次相连,中间无分支的联结方式叫电阻的串联。
A. 两个或两个以上
B. 两个
C. 两个以上
D. 一个或一个以上
【单选题】
电流流过负载时,负载将电能转换成___。
A. 机械能
B. 热能
C. 光能
D. 其他形式的能
【单选题】
电功的数学表达式不正确的是___。
A. W=Ut/R2t
B. W=UIt
C. W=U2t/Rt
D. W=I2Rt
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An administrator is configuring the Maximum Transmission Unit value on a vSphere Distributed Switch. Which two options are typical values for ESXi networking? (Choose two.)___
A. 1492
B. 1500
C. 9000
D. 9089
【多选题】
Which two configurable options apply to both virtual machine CPU and memory allocation? (Choose two.)___
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B. Shares
C. Resource Pool
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【多选题】
When attempting to power on a Virtual Machine you observe the following error: <Cannot open the disk '/vmfs/volumes/volume/vm/vm-000002.vmdk' or one of the snapshot disks it depends on.> Which three actions will be the best solutions to address this problem? (Choose three.)___
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B. Investigate the host and virtual machine log files.
C. Verify the vmdk descriptor files and if required, recreate them.
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【多选题】
An administrator has been tasked with enabling High Availability ___ on a cluster in a vSphere 6.x environment with default settings. The cluster configures properly and there are no errors. The next day when powering on a virtual machine, an error is presented: <Not Enough Failover Resources>. Which three scenarios are likely causes of this error message? (Choose three.)(CDE)
A. The default VM Monitoring Sensitivity is set too high.
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【多选题】
vMotion can be performed between which three physical boundaries? (Choose three.)___
A. Between two vCenter Server Systems
B. Between two vSphere Distributed Virtual Switches
C. Between two vCenter Server Datacenter objects
D. Between two VMware NSX Layer 4 segments
E. Between two NFS datastores
【多选题】
An administrator configures vSphere Replication for a virtual machine and enables multiple point in time (PIT) instances under the recovery settings in the Configure Replication wizard. Which two statements are correct for vSphere Replication with multiple point in time instances enabled? (Choose two.)___
A. vSphere Replication retains a number of snapshot instances of the virtual machine on the target site based on the retention policy that you specify.
B. vSphere Replication uses the virtual machine's snapshot instances to define the target site Point in Time instance based on the retention policy that you specify.
C. vSphere Replication does not support virtual machines with snapshots.
D. vSphere Replication supports virtual machines with snapshots.
【多选题】
An administrator is virtualizing a physical application server and adding it to an existing multi-tiered vApp. The application license is currently tied to the physical NIC's MAC address, so the administrator needs to ensure the license will function properly in the virtual machine. Which two actions can the administrator take to satisfy this task? (Choose two.)___
A. Set the MAC address for the vNIC in the guest operating system.
B. Install the physical server's NIC into the ESXi host.
C. Configure the MAC address for the vNIC using the vSphere Web Client.
D. Assign the physical server NIC's MAC address in the vSphere Distributed Switch.
【多选题】
Which two Fibre Channel zoning options are supported with vSphere 6.x? (Choose two.)___
A. Single-Initiator
B. Single-Initiator-Single-Target
C. Multiple-Initiators-Single-Target
D. Multiple-Initiators-Multiple-Targets
【多选题】
An administrator is attempting to remove an ESXi 6.x host from a vSphere Distributed Switch (vDS). When the administrator attempts to remove the host, the following error is observed: <The resource '16' is still in use.> What three steps are needed to successfully remove the host from the switch? (Choose three.)___
A. Select Manage Ports on the vDS for the host.
B. Locate all ports currently in use on the vDS for the host.
C. Migrate or delete any vmkernel or virtual machine adapters associated with the switch.
D. Remove all network cards from the switch before trying to remove the host.
E. Create a standard switch for everything to be automatically be migrated to.
【多选题】
Which two Virtual SAN related actions might start resynchronization of virtual machine objects? (Choose two.)___
A. Editing a virtual machine storage policy to increase the number of replicas.
B. Editing a virtual machine storage policy to reduce the number of replicas.
C. Editing a virtual machine storage policy to increase the number of disk stripes.
D. Editing a virtual machine storage policy to reduce the number of disk stripes.
【多选题】
An administrator is troubleshooting basic network connectivity issues. Which two scenarios are potential issues that this administrator might face? (Choose two.)___
A. The vSwitch is not attached to the correct physical network.
B. The portgroup is not configured to use correct VLAN.
C. Traffic shaping is configured incorrectly.
D. Jumbo frames is configured incorrectly.
【多选题】
Which three items should be validated prior to installing ESXi 6.x? (Choose three.)___
A. Remote Storage has been disconnected.
B. Installation media is available.
C. Server hardware clock is set to UTC.
D. Storage has been partitioned with a VMFS volume.
E. Network cards have been setup to use Jumbo
F. rames.
【多选题】
An administrator is performing an interactive installation of ESXi 6.x. Which three options are available for installation? (Choose three.)___
A. DVD
B. USB
C. PXE
D. Scripted
E. Auto Deploy
【多选题】
After installation of a host in your test environment, you need to move it to production. The only major change that needs to be made is that the hostname of the server needs to change. What are two ways that an administrator can change the host name without editing configuration files on the host directly? (Choose two.)___
A. Login to the Direct Console User Interface and change it from here.
B. Edit the Default TCP/IP Configuration from the vSphere Web Client.
C. Use the Ruby vSphere Client to send a script to the ESXi host that updates the hostname.
D. Update the information in DNS and the
E. SXi host will automatically update with these changes.
【多选题】
An administrator has unsuccessfully attempted several times to install an Operating System inside a virtual machine. The administrator finds that the installation fails at random intervals. Which two actions can be taken to resolve this issue? (Choose two.)___
A. Verify the md5sum and if invalid, download the installation files again.
B. Attempt the installation an additional time.
C. Attempt to use a different installation media or installation method.
D. Create a new virtual machine and attempt the installation with the existing media.
【多选题】
VMware tools is failing to install on a Microsoft Windows virtual machine. What are two possible situations that would prevent the installation? (Choose two.)___
A. The VMware tools installation media is corrupt.
B. The incorrect Operating System was selected in the virtual machine options.
C. The software prerequisites have not been installed.
D. The prerequisite services have not been started.
【多选题】
As part of a multisite Single Sign-On (SSO) deployment what two steps are required to ensure that a change to one Single Sign-On instance is propagated to the other instances? (Choose two.)___
A. Schedule a Replication Task on the primary instance
B. Select the first instance during the installation of subsequent instances
C. During the installation of each instance choose Linked-Mode
D. Enable Synchronize to Active Directory on each instance
【多选题】
You need to add an object to an existing vApp using the vSphere Web Client. How is this accomplished?___
A. Create an Object Inside the vApp.
B. Add an Object to a vApp.
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D. atastore the vApp is located in.
【多选题】
Which three steps must be taken to use vSphere Update Manager 6.x to upgrade an ESXi 5.5 host to vSphere 6.x? (Choose three.)___
A. Download an ESXi Image.
B. Configure the vSphere Update Manager Download Service.
C. Create a baseline and attach it to the ESXi Host.
D. Scan the vCenter Content Library for the
E. SXi Image.
【多选题】
Which two options would allow a database administrator, with no access to the vSphere infrastructure, to connect to a virtual machine? (Choose two.)___
A. Use the Virtual Machine Remote Console (VMRC).
B. Use Remote Desktop Protocol (RDP) to connect.
C. Ask the vSphere administrator to grant permission to access the console through vCenter Server.
D. Ask the vSphere administrator to grant permission to access with the Horizon View Direct Connect Client.
【多选题】
Which three are architecture components of vRealize Operations? (Choose three.)___
A. Identity Server
B. Administrative Server
C. Analytics Server
D. Database Server
E. Connection Broker
【单选题】
金克拉金克拉撒旦蒂萨里大儿童家爱丽丝打开就撒开绿灯技术的()
A. 手动阀手动阀
B. 撒旦
C. 反对法
D. 第三方
【单选题】
金克拉金克拉撒退热贴开绿灯技术的()
A. 是否
B. 阿斯顿
C. 撒旦
D. 感到反感
【单选题】
而非热舞法国会开绿灯技术的()
A. 撒的
B. 热个股分化
C. 返回
D. 而我认为
【单选题】
十大富豪不给发货返回返回返回()
A. dfdfgd
B. 梵蒂冈梵蒂冈
C. 广泛大概
D. 热
【多选题】
马克思主义哲学所讲的静止是指___
A. 运动的一种特殊形式
B. 绝对不动
C. 排斥运动
D. 事物处于量变状态
E. 事物在特定参考系中未发生位置变动
【多选题】
物质和运动的关系是___
A. 运动是物质的固有属性
B. 物质是运动的承担者
C. 运动是物质的存在方式
D. 运动不一定是物质的运动
E. 物质不一定都在运动
【多选题】
社会的物质性体现在___
A. 劳动是社会产生和存在的决定性因素
B. 在社会中不存在精神的现象和活动
C. 物质资料的产生是社会历史的前提
D. 全部社会生活在本质上是实践的
E. 社会生活中不存在物质关系以外的其他关系
【多选题】
意识的能动作用表现在___
A. 反映客观世界
B. 创造物质世界
C. 通过实践改造客观世界
D. 创造理论体系
E. 为自然界创造秩序
【多选题】
金克拉金克拉撒旦蒂萨里大儿童家爱丽丝打开就撒开绿灯技术的()
A. 手动阀手动阀
B. 撒旦
C. 反对法
D. 第三方
【多选题】
金克拉金克拉撒退热贴开绿灯技术的()
A. 是否
B. 阿斯顿
C. 撒旦
D. 感到反感
【多选题】
而非热舞法国会开绿灯技术的()
A. 撒的
B. 热个股分化
C. 返回
D. 而我认为
【多选题】
十大富豪不给发货返回返回返回()
A. dfdfgd
B. 梵蒂冈梵蒂冈
C. 广泛大概
D. 热
【判断题】
金克拉金克拉撒旦蒂萨里大儿童家爱丽丝打开就撒开绿灯技术的()
A. 对
B. 错
【判断题】
金克拉金克拉撒退热贴开绿灯技术的()
A. 对
B. 错
【判断题】
而非热舞法国会开绿灯技术的()
A. 对
B. 错
【判断题】
十大富豪不给发货返回返回返回()
A. 对
B. 错
【判断题】
豆腐干地方梵蒂冈热的()
A. 对
B. 错
【判断题】
豆腐干沙发沙发地方梵蒂冈热的()
A. 对
B. 错
【填空题】
金克拉金克拉撒旦蒂萨里大儿童家爱丽丝打开就撒开绿灯技术的()