8 The I/O Unit is like the security guard at the front gate. Parking(Registers)109ALUALUYou need to go to Building 10!Parking(Internal Cache)The Control Unit (CU) is like a security guard directing students to the correct building.Please wait until the road is clear, and I will open the gate!The I/O Unit is like the security guard at the front gate.
9 CISC vs. RISC Processors Complex Instruction Set CodeRISCReduced Instruction Set Code
11 Other Parts on the Motherboard System BusCMOSBIOSThe ChipsetSystem ClockExpansion SlotsFloppy and Disk Drive ConnectionsMemory
12 System Bus Metal lines (traces) connecting parts on the motherboard. Allow data to travel between devices and the CPU.Like a system of roads throughout a city.Can be expanded to other parts (like highways connecting towns and cities).
15 CMOS Chip that saves your system settings: Date and timeHardware configurationBoot device orderHas a battery so that it can save your settings even when the computer is offCMOS stands for Complex Metal Oxide Semiconductor
18 BIOS Basic Input/Output System Stores basic instructions on how the computer can talk to:KeyboardMouseMonitorMemoryAllows a computer to operate basic functions without any other software installedIs the same for ALL computers.
20 The Chipset The chipset controls most parts of the computer. It handles ‘routine’ work, so the CPU can handle more important processing.Some of the chips in the chipset include:Interrupt ControllerKeyboard ControllerDMA Controller
21 The Interrupt Controller What is an Interrupt?Lots of devices want to get the CPU’s attention;An interrupt is a signal that tells the CPU which device is calling, or sending data;The Interrupt Controller is a chip that controls the flow of data on the system bus, and lets the CPU know which device needs it;
22 Don’t worry… I can direct traffic for you! Who is trying to call me? This better be important!The CPU (Everyone wants his attention!)Don’t worry… I can direct traffic for you!The Interrupt Controller is like a police offer directing traffic at a busy roundabout.Some devices get priority over others
23 How the Interrupt Controller Works CPU123457689111013121415System ClockKeyboardFloppyPS/2 MouseInterrupt Controller
24 Common Interrupt Requests (IRQ’s) USUAL FUNCTION/DEVICESystem Timer1Keyboard22nd IRQ controller3COM2:4COM1:5Free (used by LPT2: or sound card)6Floppy disk7LPT1:8Real Time Clock (RTC)9Free (may be labeled/appear as IRQ 2)10Free (often used by sound cards)11Free12PS/2 mouse13Math coprocessor on CPU (used)14Primary IDE15Secondary IDECommon Interrupt Requests (IRQ’s)
25 Keyboard ControllerThe Keyboard Controller provides the following functions:Keyboard Control and Interpretation.PS/2 Mouse Support.Access to the High Memory Area.The Keyboard Controller is often not needed in newer computers.
26 The DMA Controller Direct Memory Access Sometimes devices may want to ‘talk’ to each other without ‘going through’ the CPU.DMA Controller controls access to the system bus, and RAM, and bypasses the CPU.
27 The CPU (Not everyone needs his attention!) I’m busy with official business… don’t bother me!The CPU (Not everyone needs his attention!)This better be important if you want to keep going down Madinat Khalifa!Thanks, officer. I guess I don’t need to bother with this car!Don’t worry, Sarge! I’ll direct this car through the roundabout!I’m only going to McDonald’s! Do I really need to go see the CPU first?Beep! Beep!The Interrupt ControllerThe DMA Controller is like a second traffic officer who handles traffic not going to the CPUCan I go now?Some devices don’t need to talk to the CPU
28 The System Clock Crystal that emits a pulse/signal. Acts like a drummer in a rock band.Pulses provide timing for the CPU and other devices.
29 Clock Speeds Measured in Hertz Speed of the Motherboard: Cycles per secondSpeed of the Motherboard:Megahertz (MHz)Speed of the CPU:Gigahertz (GHz)
30 Expansion SlotsAllow you to ‘expand’ the capabilities of your computer.Connect new circuit boards to your motherboard.Connect the data buses (roads) on the expansion cards to the system bus (roads) on the motherboard.
31 Common Expansion Cards Sound CardsModemsNetwork CardsVideo CardsSpecialty Cards
32 Types of Expansion Slots ISAIndustry Standard ArchitectureOlder, ‘legacy’ cardsPCIPeripheral Component InterconnectNewer, faster expansion cardsAGPAccelerated Graphics Port
33 Floppy and Disk Drive Connections Special slots for ‘ribbon’ (data) cables.Allow you to connect:Floppy disk drives;Hard disk drives;CD/DVD drives;Zip disk drives;Etc…
34 Floppy Drives There is usually only one floppy disk drive connection. A floppy controller chip on the motherboard controls talking to, and fuctions of the floppy drive.
35 EIDE Connections Used to connect: Two connectors on the motherboard. Hard disk drives;CD/DVD drives;Two connectors on the motherboard.Each connector can connect two devices;Up to four EIDI devices can be connected;
36 Memory Devices Hold data and instructions. Types of Memory: System Memory;RAM;ROM;
37 System Memory 1 Megabyte (1 MB) Built into motherboard. Maximum memory that could be handled by:Older PC’s;New PC’s before system drivers and OS are booted;Hold data and instructions for:System drivers;Programs used by the user;
38 Anything above 1 MBReserved for device drivers and system functionsAvailable to the user for any software
39 RAM vs. ROM RAM Examples: ROM Example: Random Access Memory Stores data and instructionsVolatileExamples:RAM chipsCMOSROMRead Only MemoryStores basic system settingsNon-volatileExample:BIOS
40 Types of Motherboards Choice of motherboard affects: Capabilities and limitations of system;Type of computer case needed;Common types of motherboards:ATATXBackplane
41 The AT Motherboard Smaller Used for classic Pentium CPU Uses SIMM RAM Uses P8 and P9 power connectors
42 The ATX Motherboard Faster Easier to install More power management featuresUses DIMM RAMHas a PI power connector
43 Backplane Motherboards Actually built into the computer case.More difficult to make upgrades.Not as popular.