Course ILT Bus structures Unit objectives Describe the primary types of buses Define interrupt, IRQ, I/O address, DMA, and base memory address Describe the features and functions of the PCI bus, and install and configure a PCI adapter card Describe the features and functions of the various video buses, and install and configure an AGP adapter card

Course ILT Topic A Topic A: Buses Topic B: Host system interaction Topic C: The PCI bus Topic D: Video buses

Course ILT Buses Communication pathway Four types –Address –Data –Expansion –Video

Course ILT PCI bus slots

Course ILT An AGP video bus slot

Course ILT The riser bus Brings the basic wiring and control of a function to a motherboard Decreases cost Three riser standards: –Advanced Communication Riser (ACR) –Audio/Modem Riser (AMR) –Communication and Networking Riser (CMR)

Course ILT Activity A-1 Examining buses

Course ILT Topic B Topic A: Buses Topic B: Host system interaction Topic C: The PCI bus Topic D: Video buses

Course ILT System interaction Gain the attention of the CPU Access shared memory locations Extend the system BIOS Transfer data across the bus

Course ILT Interrupts Signal CPU that attention is needed –CPU stops what it was doing –Services the device request –Returns to its previous task Polling –Inefficient alternative to interrupts

Course ILT Running processes

Course ILT IRQs Numerical addresses Help CPU identify interrupt source Enforce priority of interrupts Common IRQs –IRQ 1: Keyboard –IRQ2: Cascade IRQs 9-15 –IRQ4: COM1 –IRQ6: Floppy –IRQ12: PS/2 mouse –IRQ14: Primary IDE hard drive

Course ILT Assigning IRQs Manually assign for older PC designs –DIP switches –Jumpers –Proprietary software Common for conflicts Plug and Play (PnP) in new PC designs

Course ILT Device Manager - IRQs

Course ILT Activity B-1 Examining running processes and IRQ assignments

Course ILT I/O addresses Identify section of shared memory Range of memory addresses Hexadecimal

Course ILT Device Manager–I/O addresses

Course ILT Activity B-2 Viewing your computers I/O address assignments

Course ILT DMA channels DMA controller relieves CPU DMA channels Largely replaced by other techniques

Course ILT Device Manager–DMA channels

Course ILT Activity B-3 Viewing your computers DMA channel assignments

Course ILT Base memory addresses Starting memory address of BIOS extensions –Display adapters –SCSI controllers –IDE controllers

Course ILT Device Manager–Base memory

Course ILT Activity B-4 Viewing your computers base memory address assignments

Course ILT Topic C Topic A: Buses Topic B: Host system interaction Topic C: The PCI bus Topic D: Video buses

Course ILT PC/XT bus 8-bit bus –IBM PC and IBM XT 4.77 MHz clock speed 1.6 Mbps maximum data transfer rate (0.4 MBps) Supported IRQs 0-8 Configured with DIP switches or jumpers

Course ILT PC/XT card

Course ILT DIP switches and jumpers

Course ILT PC/AT and ISA bus 16-bit bus –IBM AT, clones, 80386/486, current PCs 8 MHz clock speed 8 MBps maximum data transfer rate

Course ILT ISA adapter

Course ILT ISA expansion bus slot ISA slot

Course ILT PCI bus 32- or 64-bit bus –Pentium PCs 33 or 66 MHz clock speed MBps maximum data transfer rate Up to 8 functions on a single card Up to 5 card/slots per system Requires PnP

Course ILT PCI adapter

Course ILT PCI slots

Course ILT PCIe Newer standard Uses serial communication Link Lanes x1 (by-one) x1, x2, x4, x8, x12, x16, and x32 bus widths Can up-plug Cant down-plug

Course ILT Activity C-1 Installing a PCI card

Course ILT Topic D Topic A: Buses Topic B: Host system interaction Topic C: The PCI bus Topic D: Video buses

Course ILT Need for video buses Older PC designs just used expansion bus Graphical interfaces involve massive amounts of graphics data Specialized buses developed to be fast enough

Course ILT VESA local bus 32- or 64-bit bus –Pentium PCs 33 or 66 MHz clock speed Popular on based PCs Generally software configurable No longer used

Course ILT VLB adapter

Course ILT AGP adapter Note the hook

Course ILT AGP Technically a port, not a bus 32-bit bus 33 or 66 MHz clock speed Speed pumped to as much as 533 MHz DIrect Memory Execute (DIME) MBps maximum data transfer rate PnP configurable

Course ILT Activity D-1 Installing an AGP adapter

Course ILT Unit summary Described the primary types of buses Defined interrupt, IRQ, I/O address, DMA, and base memory address Described the features and functions of the PCI bus, and installed and configure a PCI adapter card Described the features and functions of the various video buses, and installed and configure an AGP adapter card