OPERATING SYSTEM STRUCTURES OPERATING SYSTEM STRUCTURES Hardware interfaces Hardware overview System buses CPU CPU • External buses and ports AGP • Northbridge RAM Storage device interfaces • CSA Other buses around computers I2C/SMBus • Southbridge PCI temp PCI bus Audio SATA Net USB ISA bus/ SCSI FW LPC floppy MEELIS ROOS 1 MEELIS ROOS 2 OPERATING SYSTEM STRUCTURES OPERATING SYSTEM STRUCTURES System buses PCI (Peripheral Component Interface) Old PC: ISA, EISA, MCA, VLB Originally 32-bit, 33 MHz • • PnP, ISAPnP, other PnP 64-bit 66 MHz PCI • • Non-PC: VME, SBus, NuBus, Zorro II/III, TURBOChannel AGP — Advanced Graphics Port (PCI+IOMMU) • • Current: PCI family 3.3V, 5V voltages • • PCMCIA / PC Card, ExpressCard, CompactFlash, MMC/xD, . .. PCI-X (32- or 64-bit; 33, 66, 100 and 133 MHz) • • SGI: GIO32/GIO64, XIO PCI Express • • – Fast point-to-point serial interface – Up to 16 serial lanes can be used in parallel CSA — Communication Streaming Architecture • Hotplug, cPCI • MEELIS ROOS 3 MEELIS ROOS 4 OPERATING SYSTEM STRUCTURES OPERATING SYSTEM STRUCTURES External ports External buses Serial ports — RS-232, RS-422 (0.15..460 kbps) ADB — Apple Desktop Bus (10 kbps) • • Parallel port — IEEE-1284 (up to 8 Mbps) USB — Universal Serial Bus • • PS/2 — special-purpose serial ports – 1.1 and 12 Mbps (UHCI, OHCI) • – 480 Mbps (EHCI) Other special-purpose serial ports (keyboard, JTAG, . ) • FireWire (IEEE-1394) • – 400 and 800 Mbps – OHCI MEELIS ROOS 5 MEELIS ROOS 6 OPERATING SYSTEM STRUCTURES OPERATING SYSTEM STRUCTURES Storage device interfaces SCSI SCSI — Small Computer System Interface Physical layer and communication protocol are independent • • IDE (Integrated Drive Electronics) / ATA (AT Attachment) Parallel cable is the most usual physical layer • • ATAPI — ATA Packet Interface Parallel cables need termination on both ends • • FibreChannel — physical layer for SCSI, IP etc; actually a 3 types of parallel cables: • • separate network – SE — Single-Ended Serial ATA – Differential • – LVD/SE — Low Voltage Differential/Single-Ended SAS — Serial Attached SCSI • Many devices on the same bus (usually up to 8 or 16) (Ethenet) • • – Addressing: (bus, target, LUN) Synchronous and asynchronous transfers; disconnect and • reconnect TCQ — Tagged Command Queuing • MEELIS ROOS 7 MEELIS ROOS 8 OPERATING SYSTEM STRUCTURES OPERATING SYSTEM STRUCTURES Parallel SCSI cable speeds IDE/ATA standards Name speed comments Name max speed modes Narrow 5 ATA (ATA-1) 8.3 MB/s PIO 0-2, SWDMA 0-2, MWDMA 0 Fast 10 ATA-2 16.6 MB/s PIO 0-4, SWDMA 0-2, MWDMA 0-2 Fast Wide 20 ATA-3 16.6 MB/s PIO 0-4, SWDMA 0-2, MWDMA 0-2 Ultra 20 ATA-4 33 MB/s + UDMA 0,1,2 Ultra Wide 40 ATA-5 66 MB/s + UDMA 3,4 Ultra 2 40 LVD ATA-6 100 MB/s + UDMA 5 Ultra 2 Wide 80 LVD — 133 MB/s Ultra160 160 LVD (SATA-1) 150 MB/s Ultra320 320 LVD (SATA-2) 300 MB/s NCQ MEELIS ROOS 9 MEELIS ROOS 10 OPERATING SYSTEM STRUCTURES Other buses I2C, SMBus • Dallas 1-wire • SPI (Serial Peripheral Interface) • MEELIS ROOS 11.