ENGINEERING TRIPOS PART II A and EIST I

EIET LABORATORY ENGINEERING AREA ACTIVITY

Areas 5,6,7 and 8

INVESTIGATION OF THE DESIGN OF CD PLAYERS

SUBTOPIC: CD-ROM DATASTORES

1. INTRODUCTION

CD technology, first developed for audio disks, is now the basis of a high-capacity Read-Only disk system: CD-ROM. The disks themselves are similar to audio CDs, although their internal organisation is more complicated and extra Error Control Coding is used, since errors on a computer disk are more serious than errors on audio disks.

In this investigation, you will have available a typical configuration of a PC connected to an external CD-ROM drive using a SCSI (Small Computer Systems Interface) cable. To let you see signals on the SCSI cable, a 'breakout box' is provided, which allows a Logic Analyser to be connected to the cable.

The aim of this investigation is observe and explain the time taken to get data from the CD-ROM, which involves a number of components: