相关试题
【单选题】
仅具有置“0”和置“1”功能的触发器是___。
A. 基本RS触发器
B. 钟控RS触发器
C. D触发器
D. JK触发器
【单选题】
由与非门组成的基本RS触发器不允许输入的变量组合为___。
【单选题】
40仅具有保持和翻转功能的触发器是___。
A. JK触发器
B. T触发器
C. D触发器
D. T' 触发器
【单选题】
触发器由门电路构成，但它不同于门电路功能，主要特点是___。
A. 具有翻转功能
B. 具有保持功能
C. 具有记忆功能
【单选题】
TTL集成触发器直接置0端[]和直接置1端[]在触发器正常工作时应___。
A. =1，=0
B. =0，=1
C. 保持高电平“1”
D. 保持低电平“0”
【单选题】
按逻辑功能的不同，双稳态触发器可分为___。
A. RS、JK、D、T等
B. 主从型和维持阻塞型
C. TTL型和MOS型
D. 上述均包括
【单选题】
同步计数器和异步计数器比较，同步计数器的显著优点是___。
A. 工作速度高
B. 触发器利用率高
C. 电路简单
D. 不受时钟CP控制。
【单选题】
把一个五进制计数器与一个四进制计数器串联可得到___进制计数器。
【单选题】
下列逻辑电路中为时序逻辑电路的是___ 。
A. 变量译码器
B. 加法器
C. 数码寄存器
D. 数据选择器
【单选题】
47N个触发器可以构成最大计数长度{进制数}为___ 的计数器。
【单选题】
N个触发器可以构成能寄存___位二进制数码的寄存器。
【单选题】
49五个D触发器构成环形计数器，其计数长度为___。
【单选题】
同步时序电路和异步时序电路比较，其差异在于后者___。
A. 没有触发器
B. 没有统一的时钟脉冲控制
C. 没有稳定状态
D. 输出只与内部状态有关
【单选题】
一位8421BCD码计数器至少需要___个触发器。
【单选题】
某电视机水平-垂直扫描发生器需要一个分频器将31500HZ的脉冲转换为60HZ的脉冲，欲构成此分频器至少需要___个触发器。
A. 10
B. 60
C. 525
D. 31500
【单选题】
555定时器属于___
A. 时序逻辑电路
B. 组合逻辑电路
C. 模拟电子电路
【单选题】
54多谐振荡器可产生 ___
A. 正弦波
B. 矩形脉冲
C. 三角波
D. 锯齿波
【单选题】
脉冲整形电路有___。
A. 多谐振荡器
B. 施密特触发器
C. 555定时器
【单选题】
56石英晶体多谐振荡器的突出优点是___ 。
A. 速度高
B. 电路简单
C. 振荡频率稳定
D. 输出波形边沿陡峭
【单选题】
TTL单定时器型号的最后几位数字为___。
A. 555
B. 556
C. 7555
D. 7556
【单选题】
555定时器不可以组成___。
A. 多谐振荡器
B. 单稳态触发器
C. 施密特触发器
D. JK触发器
【单选题】
59以下各电路中，___可以产生脉冲定时。
A. 多谐振荡器
B. 单稳态触发器
C. 施密特触发器
D. 石英晶体多谐振荡器
【单选题】
555定时电路端不用时，应当___。
A. 接高电平
B. 接低电平
C. 通过0.01µF的电容接地
D. 通过小于500Ω的电阻接地
【单选题】
89S51的内部程序存储器与数据存储器容量各为多少？___
A. 64KB、128B
B. 4KB、64KB
C. 4KB、128B
D. 8KB、256B
【单选题】
89S51比89C51多出了哪个功能？___
A. 存储器加倍
B. 具有WDT工能
C. 多了一个8位输入/输出端口
D. 多了一个串行口
【单选题】
6在DIP40封装的8×51芯片里，复位RESET引脚的引脚编号是什么？___
【单选题】
7在DIP40封装的8×51芯片里，接地引脚与电源引脚的引脚编号是什么？___
A. 1、21
B. 11.31
C. 20、40
D. 19、39
【单选题】
9在12MHz始终脉冲的8051系统里，一个机器周期有多长？___
A. 1µs
B. 12µs
C. 1ms
D. 12ms
【单选题】
12下列哪个寄存器是8×51内的16位寄存器？___
【单选题】
14在8×51的输入/输出端口里，哪个输入/输出端口执行在输出功能时没有内部上拉电阻？___
【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
【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？___
【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
推荐试题
【多选题】
vSphere DRS helps to balance virtual machines with available resources in a vSphere cluster. What three types of resources can be taken into account for balancing? (Choose three.)___
A. CPU
B. physical NIC saturation of an ESXi host
C. virtual NIC saturation of a virtual machine
D. RAM
E. storage latency
【多选题】
Which three design requirements must be satisfied to enable RAID-6 objects in a VMware vSAN cluster? (Choose three.)___
A. vSAN Advanced license or higher
B. vSAN stretched cluster
C. at least six hosts contributing storage
D. deduplication and compression
E. all flash configuration
【多选题】
When using "Cluster resource percentage" for host failover capacity in vSphere HA Admission Control, the total resource requirements are calculated from which two values? (Choose two.)___
A. Total vCPUs assigned to each VM.
B. Average CPU usage on each VM over time.
C. Memory reservations on each VM.
D. Total memory assigned to each VM.
E. Average active memory on each VM over time.
F. CPU reservations on each VM.
【多选题】
Which are four attributes of the Active vCenter HA node? (Choose four)___
A. It uses the vCenter HA network to communicate with the Witness node.
B. It constantly replicates vPostgres data with the Witness node.
C. It uses a public IP address for the management interface.
D. It runs the active vCenter Server Appliance instance.
E. It uses the vCenter HA network for replication of data to the Passive node.
F. It provides a quorum to protect against split-brain situations.
【多选题】
Which are two vCenter Server two-factor authentication methods? (Choose two.)___
A. RSA SecurID
B. Smart Card
C. SAML
D. Symantec VIP
【多选题】
An administrator is creating VMkernel adapters on an ESXi 6.5 host and wants to create separate VMkernel adapters for every type of traffic in the default TCP/IP stack. Which three types of traffic can be explicitly enabled on a separate VMkernel adapter? (Choose three.)___
A. Virtual SAN traffic
B. NFS traffic
C. vMotion traffic
D. vSphere HA traffic
E. Fault Tolerance logging traffic
【多选题】
When migrating a Windows vCenter Server 6.0 to the vCenter Server Appliance 6.5, which two will be migrated by default? (Choose two.)___
A. Local Windows OS users and groups
B. Configuration
C. Custom ports
D. FQDN
E. Historical and Performance data
【多选题】
Which three types of Content Libraries exist within vSphere 6.5? (Choose three.)___
A. Remote Content Library
B. Published Content Library
C. Local Content Library
D. Shared Content Library
E. Subscribed Content Library
【多选题】
An administrator cannot enable multi-processor Fault Tolerance (SMP-FT) for a virtual machine. Which are two possible causes for this? (Choose two.)___
A. The virtual machine is running on a vSAN datastore.
B. The Fault Tolerance network is using a 10Gbit uplink.
C. The virtual machine has 6 vCPUs assigned.
D. The virtual machine has a 1TB VMDK attached.
E. The virtual machine has snapshots present.
【多选题】
Which two statements are true for Predictive DRS? (Choose two.)___
A. It balances resource utilization for virtual machines with unpredictable utilization patterns.
B. It integrates DRS with vRealize Operations Manager to balance workloads for virtual machines before resource utilization spikes occur.
C. It balances resource utilization based on a threshold's algorithm that runs each night.
D. It determines the best placement and balance of virtual machines based on a threshold's algorithm that runs each night in vCenter Server 6.5 Database.
【多选题】
Which two situations could cause a virtual machine to appear with (orphaned) appended to its name? (Choose two.)___
A. if a host failover is unsuccessful
B. if a virtual machine was removed from vCenter Server's inventory
C. if a virtual machine was deployed from template, and the template has been deleted
D. if a virtual machine is unregistered directly on the host
【多选题】
Which three requirements are needed to apply RAID 5 or RAID 6 erasure coding on a vSAN 6.2 or 6.5 object? (Choose three.)___
A. on Disk Format 3.0
B. Hybrid vSAN
C. All Flash vSAN
D. vSAN Advanced License
E. Stretched Cluster Configurations
【多选题】
An administrator sees the following error in the log files: Which two events could be the source of the error message? (Choose two.)___
A. vCenter Server failure
B. VXLAN failure
C. Disk array failure
D. Network failure
E. ESXi host failure
【多选题】
An administrator is attempting to access an ESXi host via the DCUI but is unable to do so. Which could be two possible causes? (Choose two.)___
A. The host in Qhas no out-of-band management capability (i.e. iLO/iDRAC).
B. The SSH service is disabled on the host.
C. Strict lockdown mode is enabled on the host.
D. Normal lockdown mode is enabled and the administrator is a member of the
E. xception User list.
【多选题】
Which two permissions are required to migrate a virtual machine with Storage vMotion? (Choose two.)___
A. Network > Move Network
B. Virtual Machine > Inventory > Move
C. Resource > Migrate powered on virtual machine
D. Datastore > Allocate Space
【多选题】
Which are three supported storage requirements for vCenter Server HA? (Choose three.)___
A. NFS
B. RDM
C. vSAN
D. VMFS
E. JBOD
【多选题】
Which are the two network requirements for a VMware vSAN 6.5 cluster? (Choose two.)___
A. Multicast must be enabled on the physical switches and routers that handle vSAN traffic.
B. vSAN requires IPv6 only.
C. All hosts must have a dedicated 40GbE NIC.
D. The vSAN network supported IPv4 or IPv6.
E. vSAN requires IPv4 only.
【多选题】
Which three prerequisites must be in place prior to enabling secure boot for a virtual machine? (Choose three.)___
A. VirtualMachine.Config.Settings privileges
B. an encrypted USB drive
C. Virtual Hardware version 13 or later
D. Virtual Hardware version 12 or later
E. EFI firmware
【多选题】
A user is given the "Virtual machine user (sample)" role in a vSphere 6.x environment. Which three permissions would the user be able to perform? (Choose three.)___
A. Reset a virtual machine.
B. Power on a virtual machine.
C. Move a host into a cluster.
D. Configure CD media.
E. Migrate a virtual machine with Storage vMotion.
【多选题】
Which three are supported upgrade processes for ESXi host? (Choose three.)___
A. using vSphere Auto Deploy
B. using a TFTP server
C. using Update Manager
D. using an
E. SXCLI command
【多选题】
When enabling Storage DRS on a datastore cluster, which three components are enabled as a result? (Choose three.)___
A. Space load balancing among datastore within the datastore cluster.
B. Initial placement for virtual disks based on space and I/O workload.
C. I/O load balancing among datastores within the datastore cluster.
D. Queue Depth alerting on disks within the datastore cluster.
E. Data de-duplication within the datastore cluster.
【多选题】
What are two features introduced in Network I/O Control version 3? (Choose two.)___
A. Bandwidth reservation per traffic type
B. Network resource pools
C. CoS tagging
D. Bandwidth guarantee to virtual machines
【多选题】
Which two correct virtual machine advanced configuration parameters will accomplish this? (Choose two.)___
A. isolation.device.edit.disable = “FALSE”
B. isolation.device.edit.disable = “TRUE”
C. isolation.device.connectable.disable = “FALSE”
D. isolation.device.connectable.disable = “TRUE”
【多选题】
Which three statements are correct regarding booting an ESXi Host from Fibre Channel SAN? (Choose three.)___
A. Direct connect topology is supported.
B. Each host must have its own boot LUN.
C. ESXi hosts do not require local storage.
D. Multipathing to a boot LUN on an active-passive array is supported.
E. Hosts can share one common boot LUN.
【多选题】
Which two tasks should a vSphere administrator perform if the vmkernel log reports VMFS metadata errors? (Choose two.)___
A. contact VMware technical support
B. reformat the datastore
C. check the device with VOMA
D. ignore the messages
【多选题】
Which two statements are true for a vCenterServer user account that is used for vSphere Data Protection (VDP)? (Choose two.)___
A. The user account must be assigned with Administrator role.
B. The password for the user account cannot contain spaces.
C. The user account should be created in the Single Sign-On domain
D. The user account cannot inherit required permissions from a group role.
【多选题】
Which three storage protocols are supported by Virtual Volumes? (Choose three.)___
A. FCIP
B. FCoE
C. iSCSI
D. NFS v3
E. NFS v4
【多选题】
A vSphere administrator observes a CPU spike on one of the web servers (view the Exhibit.) Which two statements can describe the cause of this activity? (Choose two.)___
A. The network packet size is too large.
B. VMware Tools is not installed.
C. Disk latency is present on the datastore.
D. The network packet size is too small.
【多选题】
Which three operations can cause VMFS metadata updates? (Choose three.)___
A. Restarting a VM using the guest OS.
B. Launching a VM console.
C. Migrating a VM with vMotion.
D. Powering a VM on or off.
E. Expanding a VMFS datastore.
【多选题】
*What two services run on all nodes in a vCenter Server HA cluster? (Choose two.)___
A. vmware-vmon
B. vmware-vpostgres
C. vmare-rbd-watchdog
D. vmware-vcha
【多选题】
Which two statements are true regarding Auto Deploy in version 6.5? (Choose two.)___
A. Auto Deploy can be configured and managed via PowerCLI.
B. Auto Deploy can be configured and managed via the vSphere Client.
C. Auto
D. eploy can be configured and managed via the vSphere Web Client.
【多选题】
What three options can improve network performance for a virtual machine? (Choose three.)___
A. MLD
B. TSO
C. NetFlow
D. LRO
E. SR-IOV
【多选题】
Which two storage technologies are supported for MSCS? (Choose two.)___
A. NFS
B. VAAI
C. iSCSI
D. FC
【多选题】
When upgrading a VMware vSAN cluster to version 6.5, which two tasks must be completed to comply with upgrade requirements and VMware-recommended best practices? (Choose two.)___
A. Use RVC to upgrade the hosts.
B. Use the latest available ESXi version.
C. Back up all VMs.
D. Use only the “Full data migration” maintenance mode option.
【多选题】
What two enhancements are in VMFS6 but not in VMFS5? (Choose two.)___
A. Support for 4k native disks
B. Support for 512e disks
C. GPT storage device partitioning
D. Automatic space reclamation
【多选题】
Which two statements describe why a vSphere DRS cluster would report load imbalance? (Choose two.)___
A. The configured migration threshold is too high.
B. The configured migration threshold is too low.
C. DRS is configured for Partially Automated.
D. Enhanced vMotion Compatibility (EVC) is enabled.
【多选题】
A vSphere Administrator must ensure that vCenter Server service is running in a domain user account rather than Local System Account. To accomplish this, the user account should have which two permissions? (Choose two.)___
A. Log on as a service.
B. Act as part of the operating system.
C. Log on as a batch job.
D. Log on locally.
【多选题】
A virtual machine fails to power on after being deployed from a template. What two remediation steps could correct this issue? (Choose two.)___
A. Increase CPU reservation
B. Decrease memory reservation
C. Increase memory reservation
D. Increase datastore capacity
E. Decrease CPU reservation
【多选题】
Which three directories are available under the vcsa-cli-installer folder of the vCenter Server Appliance installation media? (Choose three.)___
A. \mac
B. \ovftool
C. \migration-assistant
D. \win32
E. \lin64
【多选题】
What are three considerations when booting ESXihost from SAN software FCoE? (Choose three.)___
A. The VMware_FCoE_vSwitch that the installer automatically created cannot be changed.
B. Boot LUN cannot be shared with other hosts even on shared storage.
C. Multipathing is not supported at pre-boot.
D. Software FCoE boot configuration cannot be changed from within
E. SXi.
