This chapter and the next chapter discuss IDE and SCSI interfaces which are used to interface to disk drives and mass storage devices. Disks are used to store data reliably in the long term. Typical disk drives either store binary information as magnetic fields on a fixed disk (as in a hard disk drive), a plastic disk (as in a floppy disk or tape drive), or as optical representation (on optical disks).
The main sources of permanent read/writeable storage are:
• Magnetic tape – where the digital bits are stored with varying magnetic fields. Typical devices are tape cartridges, DAT and 8 mm video tape.
• Magnetic disk – as with the magnetic tape the bits are stored as varying magnetic fields on a magnetic disk. ...