Block format and disk layout on cd-rom, Computer Engineering

Assignment Help:

Q. Block Format and Disk Layout on CD-ROM?

A typical block format is displayed in Figure (a). It comprises the subsequent fields:

  • Sync: Sync field identifies beginning of a block. It comprises a byte of all 0s, 10 bytes of all 1s and bytes of all 0s.
  • Header: The header comprises block address and mode byte. Mode 0 specifies a blank data field and mode 1 specifies use of an error-correcting code and 2048 bytes of data as well as mode 2 specifies 2336 bytes of user data with no error correcting code.
  • Data: User data.
  • Auxiliary: Extra user data in mode 2. In mode 1 this is a 288-byte error correcting code.

2220_Block Format and Disk Layout on CD-ROM.png

Figure: Block Format and Disk Layout on CD-ROM

However what is Min (Minute), Sec (Second) and Sector fields in Header field?  The sectors of CD-ROM aren't arranged like sectors in hard disks (Please see Figure (b)). Rather they are all equal length segments. If we rotate CD drive at constant speed the linear velocity of disk surface movement will be higher at the outer side than that of centre portions. To offset this liner speed gap either we store less data on outer sectors or we decrease speed of rotation while reading outer tracks. CD follows later approach which is instead of moving CD drive at constant velocity. It's rotated at variable velocity. Speed or rotation of disk decreases as we move away from centre such that sector's can be read in constant time. This method of reading is known as Constant Liner Velocity (CLV).


Related Discussions:- Block format and disk layout on cd-rom

Explain public switched telephone network, Explain Public Switched Telephon...

Explain Public Switched Telephone Network. PSTN (Public Switched Telephone Network): This is Public Switched Telephone Network (PSTN), which accommodates two types of subscri

Perform binary addition, Q. Explain the following: a. BCD code b. Gra...

Q. Explain the following: a. BCD code b. Gray code c. Excess-3 code d. True complement method Q. Addition-Subtraction-Multiplication-Division: Perform Binary Addi

Differentiate between exception and validation testing, Differentiate betwe...

Differentiate between exception and validation testing. - Validation testing is done to test the software in conformance to the needs specified. It aims to demonstrate that the

What is actor, What is actor? An actor is a direct external user of a s...

What is actor? An actor is a direct external user of a system. Every actor shows objects that behave in a particular way towards systems. Actors are directly linked to system.

Describe the advantages of java servlets over cgi interface, Describe the a...

Describe the advantages of JAVA servlets over CGI interface. The Advantage of Servlets Over "Tradi tional" CGI: Java servlets are extra efficient, easier to utilize more pow

What is a development class, What is a Development class? Related obje...

What is a Development class? Related objects from the ABAP/4 repository are assigned to the similar development class.  This enables you to right and transport related objects

What do you mean by instruction cycle, Q. What do you mean by instruction c...

Q. What do you mean by instruction cycle? We have considered the instruction execution in previous section. Now let's consider more about different types of instruction executi

Explain register indirect addressing, Q. Explain Register Indirect Addressi...

Q. Explain Register Indirect Addressing? In this addressing technique the operand is data in memory pointed to by a register. Or we can say in other words that the operand fie

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd