IDE and SCSI Devices Terms and Definitions Chapter Objectives After completing this chapter you will Understand hard drive terminology Understand the different hard drive types Be able to set up and configure different types of hard drives Be able to troubleshoot hard drive problems Understand and be able to perform hard drive preventive maintenance Hard Drive Overview Hard drives are the most popular devices for storing data The hard drive subsystem can have up to three parts The hard drive Cables that attach to an adapter or the motherboard Control circuits located on an adapter or the motherboard Hard Drive Geometry Components of a Hard Drive Platters are multiple hard metal surfaces contained in the hard drive Read Write Heads write and read 1s and 0s to and from the hard drive surface A Head Crash occurs when a read write head touches the hard drive platter Track is a concentric circle on a formatted floppy or hard drive platter Cylinder is one corresponding track on all surfaces of a hard drive Sectors Each track is divided into sectors which contains 512 bytes of data ZBR Zone Bit Recording efficiently uses the hard drive surface by placing more sectors on the outer tracks than on the inner tracks Interleaving is a method of numbering sectors for the most efficient transfer of data between the hard drive and the controller Today s hard drives normally use a 1 1 interleave Hard Drive Geometry Hard Drive Geometry IDE SCSI Figure 1 Hard Drive Geometry Cylinder vs Tracks IDE SCSI Figure 2 Hard Drive Geometry Sectors on Older Hard Drives IDE SCSI Figure 3 Hard Drive Geometry Zone Bit Recording Sectors IDE SCSI Figure 4 Hard Drive Geometry 3 1 Interleaving IDE SCSI Figure 5 Hard Drive Interfaces Overview There are four hard drive interfaces ST506 ESDI IDE ATA SCSI Encoding is the way 1s and 0s are placed on the drive IDE Integrated Drive Electronics IDE Integrated Drive Electronics is the most popular type of hard drive used in home and business computers DMA Direct Memory Access allows data transfer between the hard drive and RAM without going through the CPU PIO Programmed Input Output is a speed standard for data transfers to and from the hard drive UDMA Ultra DMA allows the IDE interface to control the PCI bus for faster transfers SMART Self Monitoring Analysis Report Technology is part of the ATA 3 IDE standard for power management drive analysis and failure reporting CRC Cyclic Redundancy Checking is an advanced method of checking the data for errors ATAPI AT Attachment Packet Interface is the hardware side of the IDE specification that supports devices like CD and tape drives Serial ATA is a point to point interface in which each device connects to the host through a dedicated link and has the entire interface bandwidth IDE Integrated Drive Electronics PIO Modes for IDE Hard Drives IDE SCSI Table 1 IDE Integrated Drive Electronics DMA Modes for IDE Hard Drives IDE SCSI Table 2 IDE Integrated Drive Electronics 80 and 40 Pin Conductor Cable IDE SCSI Figure 6 IDE Integrated Drive Electronics IDE ATA Standards IDE SCSI Table 4 SCSI Small Computer System Interface SCSI Small Computer System Interface is an interface standard that connects multiple small devices to the same adapter via a SCSI bus SCSI bus is the bus shared by all devices that attach to one SCSI adapter Host Adapter connects the SCSI device to the motherboard and coordinates the activities of other devices connected SCSI Small Computer System Interface SCSI Standards IDE SCSI Table 5 Laptop Storage Devices Laptops can use IDE or SCSI hard drives Laptop IDE hard drives are installed using two methods Proprietary installation is installed in a location that cannot be changed configured or moved very easily Removable IDE hard drives with a laptop are installed or removed through a 44 pin connector SCSI Software Standards Most SCSI hard drives have software built into the hard drive s BIOS chip Other drives must use one of three types of SCSI software standards ASPI Advanced SCSI Programming Interface CAM Common Access Method LADDR Layered Device Driver Architecture Drive Configuration Overview The configuration of a hard drive usually includes setting jumpers on the drive terminating properly and performing a few software commands IDE Device Configuration IDE Hard Drives are normally configured using jumpers Single IDE setting is used when only one devices connects to the IDE cable Master IDE setting is a jumper setting used to configure an IDE device and is the controlling device on the interface Slave IDE setting is an IDE setting for the second device added to the IDE cable The device should be a slower device than the master Cable Select is a setting used on IDE devices when a special cable determines which device is the master and which one is the slave DASP Drive Active Slave Present is a signal in the ATA interface of the IDE connector that is used to indicate the presence of a slave IDE device Master Slave configuration can be found on 9 19 IDE Device Configuration IDE Motherboard Connectors IDE SCSI Figure 7 IDE Device Configuration IDE Hard Drive Set as Master IDE SCSI Figure 8 IDE Device Configuration Two IDE Hard Drives IDE SCSI Figure 9 Serial ATA SATA Installation Serial ATA drives are easy to install Serial ATA drives do not have any master slave cable select or termination settings Uses a small 7 pin connector that attaches between the serial ATA controller and the serial ATA drive Installation instructions for serial ATA drives can be found on 9 25 Serial ATA SATA Installation Installed SATA Hard Drive and Adapter IDE SCSI Figure 12 SCSI Configuration A SCSI device is configured by Setting the proper SCSI ID Terminating both ends of the SCSI chain Connecting the proper cables A SCSI ID is the priority number assigned to each device connected by a SCSI chain SCSI ID Configuration Standard SCSI devices recognize SCSI IDs 0 through 7 Wide SCSI devices recognize SCSI IDs 0 through 15 Power on all external SCSI devices before powering on the computer Each SCSI device must have a unique SCSI ID SCAM SCSI Configured AutoMatically allows for automatic SCSI ID assignment SCSI ID Configuration SCSI ID Settings Most Significant Bit to the Left IDE SCSI Table 7 SCSI ID Configuration Two Internal SCSI Devices SCSI IDs IDE SCSI Figure 13 SCSI ID Configuration Two External SCSI Devices SCSI IDs IDE SCSI Figure 14 SCSI Termination SCSI termination is performed in several different ways By installing a SIPP By