Tài liệu Troy Technologies USA_ A+ CERTIFICATION STUDY GUIDE Core Exam doc

Troy Technologies USA A+ CERTIFICATION STUDY GUIDE Core Exam Edition 4 Congratulations!! You have purchased one of the Troy Technologies USA Study Guides. This study guide consists of a selection of questions and answers similar to the ones you will find on the official A+ Core Certification exam. All you need to do is study and memorize the following questions and answers and you will be ready to take the exam. Remember, we guarantee it! Average study time is 10 to 15 hours. Then you are ready. GOOD LUCK! Guarantee Should you use this study guide and still fail the exam, then send us the original of your official score notice, along with your mailing address to: Troy Technologies USA 8200 Pat Booker Rd. #368 San Antonio, TX 78233 We will gladly refund the cost of this study guide. However, you are not going to need this guarantee if you follow the above instructions. This material is protected by copyright law and international treaties. Unauthorized reproduction or distribution of this material, or any portion thereof, may result in severe civil and criminal penalties, and will be prosecuted to the maximum extent possible under law.  Copyright 1998, 1999 & 2000 Troy Technologies USA. All Rights Reserved. . 1 Microprocessors CPU - The heart of the Microprocessor is the Central Processing Unit (CPU). The CPU controls nearly all functions of the PC. External Data Bus - Wires on the motherboard used by the CPU to communicate with peripherals and ROM. Address Bus - Wires on the motherboard used by the CPU to communicate and access memory through the Memory Controller Chip (MCC). How much memory a CPU can access depends on how many wires are in the address bus. Clock Speed - The speed at which a CPU can perform calculations and access peripherals or memory. This is controlled by the oscillating System Crystal located on the motherboard. Types of CPU packages CPU System DIPP (Dual Inline Pin Package ) 8088, 8086, 80286 PGA ( Pin Grid Array) 80286, 80386, 486 Pentium, P6 PLCC (Plastic Leaderless Chip Carrier) 80286, 80386 PQFP (Plastic Quad Flat Pack) 80286, 80386, 486 Real Mode - The mode of memory access used by the CPU in DOS. CPU can only access 1MB of memory and can only run one program at a time. Protected Mode - The mode of memory access used by the CPU to address more than 1MB of memory and run more than one program at a time by “protecting” the part of memory each program is running in from use by another program. 386 Enhanced Mode - Same as protected mode, but added the enhanced features of Virtual Memory and Virtual 8086. Virtual Memory - When CPU uses a portions of a hard drive storage device as memory. Appears just like regular memory to the operating system. Math Coprocessor - A processor other than the CPU that is used to perform high level math functions. Internal Cache - On board RAM built into the CPU. This allows the CPU to store commands internally and execute them when it has time. Also called Level one (L1) cache. External Cache - The same as L1 cache, only it is a special RAM chip that sits on the motherboard. CPU Advancements CPU Introduced 80286 Protected Mode, Addressed more than 1MB of memory (16MB) 80386DX/SX/SL Virtual Memory, Virtual 8086, Internal Cache, 386 Protected Mode 486 Built in Math Coprocessor & L1 Cache on same chip Pentium Dual Pipelining Pentium Pro (P6) Quad Pipelining, Dynamic Processing, L1 &L2 cache on board 2 Memory Random Access Memory (RAM) - The working area of your PC where programs are stored while being executed. DRAM - Dynamic Random Access Memory. Typically the type of RAM accessed by the CPU in most PC. Uses capacitors to store data, so it must be refreshed constantly. Access Speed - The number of nanoseconds it takes the DRAM chip to respond to the MCC. This is typically 80ns to 50ns. The lower the number, the faster the chip. Access speed can be determined by looking at the last number on the chip. Ex: AAA4M303J - 06, would be 60ns. Parity - A method of memory error detection. Usually manifests itself as an extra chip on the memory SIMM. SRAM - Static RAM. Does not use capacitors, so it does not have to be refreshed like DRAM. It is very expensive, so it is only used in small amounts for memory cache. RAM Memory Packages Package Features SIPP (Single Inline Pin Package) Combined 8 DRAM chips on a single card 8 bits wide SIMM (Single Inline Memory Module) Eliminated pins, Introduced Banking, 30 or 72 pin flavors DIMM (Dual Inline Memory Module) 168 pins per stick Conventional Memory - The first 640K of memory addresses used to run applications. Also referred to as Lower Memory. Reserved Memory - The next 384K of memory address reserved for use by different types of ROM BIOS and Video RAM. Also referred to as Upper Memory. Extended Memory (XMS) - Any memory addresses above Reserved Memory. High Memory Area (HMA) - The first 64K of Extended Memory Expanded Memory (EMS) - Reserved or Extended Memory which is made to act like Conventional Memory. Also known as LIM Memory. Limulation - The act of converting Extended Memory into Expanded Memory. Shadowing - The process of copying ROM BIOS information into the Reserved Memory area of RAM. HIMEM.SYS - A device driver created to open up the HMA by unmasking the A20 wire, and act as a gateway to Extended Memory. Directs all applications where to go in Extended Memory to avoid conflicts with other applications using Extended Memory. There is a version for both DOS and Windows. Extended memory cannot be accessed unless HIMEM.SYS is running. Upper Memory Blocks (UMB) - Unused memory addresses in the Reserved Memory area. EMM386.EXE - DOS’ Memory Manager program. Performs Limulation and opens up the UMBs so that device drivers and programs can be loaded via CONFIG.SYS or AUTOEXEC.BAT. EMS Page Frame - A 64K block of memory addresses in the Reserved Memory area used to perform Limulation. 3 MEMMAKER - DOS utility that will free up Conventional Memory by loading as many devices into UMBs as possible. MEM - DOS command that lets you view the status of all memory. The /C switch classifies all your memory and shows all programs load in Conventional and Upper Memory. Map of RAM Memory Addresses Map of Reserved Memory EMM386 Common Load Options Statement Actions DEVICE C:\DOS\EMM386.EXE NOEMS Allows access to Upper Memory, but prevents access to EMS. DEVICE C:\DOS\EMM386.EXE X=C800-C9FF Excludes the specified memory addresses for loading device drivers or programs. DEVICE C:\DOS\EMM386.EXE I=F000-F3FF Includes memory addresses specified as an area where device drivers and programs can be loaded. EXTENDED MEMORY (XMS) *CAN BE EXPANDED MEMORY (EMS) HMA RESERVED/UPPER MEMORY CONVENTIONAL MEMORY INFINITE 110000 10FFFF 100000 FFFFF A0000 9FFFF 00000 SYSTEM BIOS FFFFF F0000      OPTIONAL   BIOS   AREA      EFFFF C8000 VIDEO BIOS C7FFF C0000 COLOR TEXT BFFFF B8000 MONO TEXT B7FFF B0000 EGA/VGA GRAPHICS AFFFF A0000 4 BIOS Motherboard - Provides common access to the external data and address buses for all devices in the computer. Basic Input/Output Services (BIOS) - All the small programs used to communicate with the PCs internal devices in order to perform input and output services. These programs are usually stored on a ROM chip. System BIOS - The BIOS stored on a ROM chip soldered to the motherboard which is never changing and control the core PC devices. Complimentary Metal-Oxide Semiconductor (CMOS) - A chip located on the motherboard that contains data used by the System BIOS in system configuration. This information is updatable requires constant power to keep it from losing information. CMOS Battery - A small battery mounted on the motherboard which provides power to the CMOS when the PC is turned off. Power On Self Test - A special program initiated when the computer is started or reset. This program performs a self diagnostic on all devices. Common POST Numeric Error Codes Error Code Problem 301 Keyboard Error 1701 Bad Had Drive Controller 7301 Bad Floppy Drive Controller 161 Dead Battery 1101 Bad Serial Card You may be required to identify the locations of certain components on a motherboard diagram. Be familiar with where the processor, CMOS (Real-time clock), Cache and keyboard controller are located. 5 Hard Drives Geometry Geometry is the internal electronic organization of data on the hard drive. This geometry consists of 5 numerical values. Heads, Cylinders, Sectors/Track, Write Precomp, Landing Zone. Heads - The total number of sides of all the platters used to store data. Three platters would have 6 Heads. The maximum number of Heads in any hard drive is limited to 16 by the System BIOS. Cylinders - Hard drives store data in circular paths on each platter surface (Head). These paths are called tracks. There are hundreds of circular tracks on each Head. Starting from the inner most track, each outer track is slightly larger in diameter. If you had platters stacked one on top of the other is your hard drive, then a Cylinder would be a set of tracks that were exactly the same diameter on each platter surface (Head). So if you had three platters your Cylinder would consist of 6 tracks. 1024 is the maximum Cylinders you can have on a hard drive according to the System BIOS. Sectors/Track - A Sector is the smallest portions that a Track can be divided into. The number Sectors that you divide your Tracks into is called the Sectors per Track, or Sectors/Track The maximum numbers of Sectors per Track you can have is limited to 63 by the System BIOS. Sectors can only hold 512 bytes of data, no matter how many Sectors you divide your Track into. Write Precomp - This is now obsolete, but many older hard drives still use it. The Write Precomp value determines the Cylinder where “write precompensation” starts. Landing Zone - This is also obsolete today. But on older hard drives the Landing Zone value designated an unused Cylinder as a parking place for the read/write head. Low Level Formatting - The actions performed to actually create all the sectors, tracks, cylinder and head information on a hard drive. The maximum size of hard drive that can be supported by System BIOS is 528 Million Bytes (16 X 1024 X 63). PIO Mode - Programmable Input/Output Mode is the standardized protocol which ATA drives use to transfer data to and from memory. All ATA drives can use PIO Modes 0, 1, & 2. PIO Modes Mode Transfer Rate per second 0 3.3 MB 1 5.2 MB 2 8.3 MB 3 11.1 MB 4 16.6 MB IORDY - The CMOS setting that allows the transfer rate to slow down as the head moves across the disk. Only used in conjunction with PIO Mode 3 or 4. Hard Drive Interface Type ST506 - This was the first hard drive standard introduced by Seagate in 1980. This type drive had to be physically installed, then you had enter the CMOS configuration. After that you had to low-level format the drive and then partition it. Finally, you had to perform your high level format. 6 ESDI - Enhanced Small Device Interface hard drive was introduced in 1983. Incorporated the hard drive controller on the drive itself. Configuration was just like the ST506 drives. The high cost made them obsolete. IDE - Integrated Drive Electronic hard drive, also known as ATA/CAM, standard was introduced in 1989. This was a device that uses a 40 pin cable and required no low level formatting. IDE drives use “sector translation”, which allow you to change the drives geometry in CMOS. This allows you to circumvent the System BIOS limitations on the physical size of your hard drive by letting you specify Logical Block Addressing (LBA). IDE drives use PIO Mode 0, 1, or 2. EIDE - Enhanced IDE hard drives introduced a number of improvements to the IDE standards and has become the standard PC drive type used today. EIDE standard supports up to 4 EIDE devices, including CD-ROMs. Also allowed ATA drives to use PIO Modes 3 and 4. FAST ATA - Seagate’s answer to the EIDE drive. Basically the same standard. SCSI - Small Computer System Interface drives are the newest type hard drive interfaces to appear. SCSI can allow up to 7 devices (8 of you count adapter card) daisy chained together on one controller. Partitioning Any one physical hard drive can be partitioned into up to 24 Logical hard drives. Partitioning makes data storage more efficient and allows you to install more than 1 operating system on your PC. FDISK - A DOS utility that is used to partition a PC hard drive. Active Partition - The partition the BIOS will look on for the operating system. Primary Partition - The partition where DOS is stored. This partition must always be labeled C:. Extended partition - Any partition that is not a Primary Partition. High Level Formatting Commonly called just “formatting”, this is where the File Allocations Table (FAT) and root directory are created. The DOS FORMAT.COM utility is used to perform this function. File Allocation Table (FAT) - A table on the disk that keeps track of which file is stored in which sector. Hard drives use a 16-bit FAT, while Floppy Drives use a 12-bit FAT. The format command will write the status code 0000 to identify all good sectors or status code FFF7 to identify bad sectors to the FAT. Clustering - A more efficient way of building a FAT by combining a set of contiguous sectors and treating them as a single unit in the FAT. This is now standard practice and makes the cluster the basic unit of storage, instead of the sector. Fragmentation - When a file is written to several different cluster that are not contiguous on the drive. Fragmentation slows down access time because the read/write heads have to travel all over the drive to reassemble all the different fragments. Buses The are basically two types of buses that is used to transfer data and instructions on a PC motherboard. The External Data Bus or System Bus, described above, and the Expansion Bus. 7 Expansion Bus - The part of the External Data Bus that is connected to the PC expansion slots. The Expansion Bus has its own crystal which allows it to run as a different clock speed than the External Data Bus. Expansion Slots - Expansion slots are used to add adapter cards for new devices to the PC. I/O Address - A unique range of 16-bit hexadecimal addresses assigned to devices in order for them to communicate with the CPU. IRQ - A mechanism used by devices to send an interrupt message to the CPU so that it will stop what it is doing and talk to them. This is done by allowing the device to send a message via its Interrupt Request Wire (IRQ) to the CPUs INT wire. Each devices IRQ wire must be assigned a number to uniquely identify that device. DMA - Direct Memory Access chip is a crude CPU type device that moves data, that the CPU does not need to see, between RAM and peripherals. This relieves the CPU of this routine task so it can function more efficiently. There are 8 DMA channels that can be used on most PCs (0-7). Device Interface Settings IRQ I/O Address DMA Device 0 0040-0043 System timer 1 0060-0063 Keyboard 2 * Cascade to IRQ 9 (map to 9) 3 02F8-02FF Com2 3 02E8-02EF Com4 4 03F8-03FF Com1 4 03E8-03EF Com3 5 0278-027F LPT2 6 03F0-03F7 2 Floppy Controller 7 0378-037F LPT1 8 0070-0071 Real Time Clock (RTC) 9 * Cascade to IRQ 2 (map to 2) 10 Available 11 Available 12 Available 13 00F0-00FF Math Co-Processor 14 01F0-01FF Primary Hard Drive Controller 15 0170-0177 Secondary Hard Drive Controller Types of Expansion Slots Slot Bus Size ISA (Industry Standard Architecture) 8 or 16-bit Slowest slot used today MCA (Micro-Channel Architecture) 16 or 32-bit Expensive, Fast, and Dead technology EISA (Enhanced ISA) 32-bit Compatible with ISA Slots VL-Bus (VESA Local Bus) 32-bit Bus Mastering, Uses ISA Slots with special connector PCI (Peripheral Component Interconnect) 32-bit Bus Mastering, Uses PCI Slots, Has a unique additional bus. PCI-2 64-bit Bus Mastering, Uses PCI Slots, Has unique additional bus. 8 Types of PCMCIA CARDS Card Size Type 1 3.5 millimeters Type 2 5.0 millimeters Type 3 10.5 millimeters SCSI SCSI ID - SCSI devices can be chained together and controlled by a single adapter. Each device must have a unique ID. ID numbers range from 0 to 7 for 8-bit SCSI and 0-15 for 16-bit SCSI. Termination - A SCSI chain must be terminated at each end. Devices that are not on the ends of the chain must not be terminated. Improper termination can cause damage to SCSI devices and adapters. ASPI - Advanced SCSI Programmers Interface was developed to provide a standard for uniform compatibility of SCSI devices. If you are running ASPI drivers on your PC, then you can disable the ROM BIOS that is present on most SCSI adapter cards, unless you are booting from a SCSI hard drive. SCSI Types Types Data Bits Clock Rate Max Data Rate IDs SCSI-1 8 5MHz 5MB 8 SCSI-2 8 5MHz 5MB 8 Wide SCSI 16 5MHz 10MB 16 Wide SCSI 32 5MHz 20MB 16 SCSI-2 Fast 8 10MHz 10MB 8 Fast & Wide SCSI 16 10MHz 20MB 16 Fast & Wide SCSI 32 10MHz 40MB 32 Ultra SCSI 8 20MHz 20MB 8 Ultra Wide SCSI 16 20MHz 40MB 16 Printers There are basically 3 types of Printers that can be connected to your PC. Early printers used Serial communication (1-bit at a time). However, most all printers today use Parallel communication (8-bits at a time). Most all printers use the same type of parallel cable with a DB25 connector at one end and a 36 pin Centronics connector at the other. Types of Printers Printer Description Impact Daisy Wheel or Dot Matrix (9 or 24 pins) Ink Jet Spray in on paper Laser Write with a laser. Also call Electrographic Printers (EP) Printer Languages Language Description ASCII A standard set of commands with limited printer control functions. PCL (HP Printer Control Language) HP’s own hardware dependent printer language. Postscript PDL (Page Description Language) A hardware independent language capable of high resolution graphics. [...]... smear easily Using what you know about the EP process, what assembly would you suspect? A: Fuser 94: What was the first CPU to come with a built-in coprocessor? A: 486DX 95: DC2000, DAT, and QIC80 are all examples of what? A: Tape media 96: What type of motherboard has a soft power-on switch? A: ATX 97: What occurs during the writing part of the EP print process? A: An image of 0Vdc charge is ‘written’... connected, or a disk drive with no disk in it 162: How can you disable bus mastering for a PC card? A: BIOS on the card 163: Which of the following items would require you to comply with EPA disposal guidelines? A: Battery 164: The ESD wrist strap is designed to protect PC Components or Service Technicians ? A: Both 165: Which processor uses slot 1? A: Pentium II 166: What does the term BIOS stand... Head to disk interference 264: With a dot matrix printer, light then dark print is most commonly caused by? A: Erratic ribbon advancement 265: Your client gets garbage characters when trying to print a document Which of the questions listed below could you ask? (choose all that apply) A: Occurrence (how often)? Do you have a sample? What applications are being used? Where is the printer located? 266: . Troy Technologies USA A+ CERTIFICATION STUDY GUIDE Core Exam Edition 4 Congratulations!! You have purchased one of the Troy Technologies USA Study Guides this study guide and still fail the exam, then send us the original of your official score notice, along with your mailing address to: Troy Technologies USA