· What is Hard Disk?
– Stores data in magnetic disk like medium
· Non-volatile mass storage device.
· Has very high access time as compared to RAM (10-20 million ns).
· Very cheap as compared to RAM and so large in capacity.
· Interface standards
– IDE (Integrated Drive Electronics)
∗ The hard disk drive includes the drive controller circuitry and hence known as IDE.
∗ It can support atmost 4 devices.
∗ 16 bit interface standard; 40 pin/80 pin connector.
∗ ATA-33/66
· Interface standards contd…
– SCSI (Small Computer System Interface)
∗ General pupose interface standard used for connecting many types of devices to the PC.
∗ Supports 7 to 15 different devices like hard disk, scanner, CD ROM etc.
∗ 32 bit interface standard and more expensive than IDE.
∗ Allows simultanous access for faster data transfer.
· Connecting Multiple IDE Harddisks/CD-Roms
– Primary/Secondary and Master/Slave settings – Jumper settings
· Performance parameters
– Rotation speed.
– Average seek time.
