Memory in a flash!

Flash memory is type of non-volatile memory that can be electronically erased and reprogrammed. Its name was invented by Toshiba to express how much faster it could be erased – “in a flash”, which means “very quickly”.

Unlike RAM, which is volatile, flash memory retains the information stored in the chip when the power is turned off. This makes it ideal for use in digital cameras, laptops, network switches, video game cards, mobile phones and portable multimedia players. In addition, it offers fast read access times (although not as fast as RAM), with transfer rates of 12MB per second. Unlike ROM chips, flash memory chips are rewritable, so you can update programs via software.

Inside the chip, data is stored in several floating gate transistors, called cells. Each cell traditionally stores one bit of data (1= erased and 0= programmed). New devices have a multi-level cell structure so they can store more that one bit per cell. The chips are constructed with either NOR or NAND gates. NOR chips function like a computer’s main memory, while NAND works like a hard drive. For example, in a camera, NOR flash contains the camera’s internal software, while NAND flash is used to store the images.

Flash memory is used in several ways:

- Many PCs have their BIOS (basic input/output system) stored on a flash memory chip so it can be updated if necessary.

- Modems use flash memory because it allows the manufacturer to support new protocols.

- USB flash drives are used to save and move MP3s and other data files between computers. They are more easily transported than external hard drives because they use solid-state technology, meaning that they don’t have fragile moving parts that can break if dropped. However, USB flash drives have less storage capacity than hard drives.

New U3 smart drives allow users to store both applications and data. They have two drive partitions and can carry applications that run on the host computer without requiring installation.

Flash memory card are used to store images on cameras, to back up data on PDAs, to transfer games in video consoles, to record voice and music on MP3 players or to store movies on MP4 players. They are as small as a stamp, and capacity can range from 8MB to several gigabytes.

The only limitation is that flash cards are often not interchangeable between devices. Some format include: CompactFlash, Secure Digital, MultiMedia Card, miniSD card, and xD-Picture Card. Sony has its own product called the Memory Stick, used in its digital still cameras, video camcorders and the PlayStation Portable. The photos stored in a digital camera can be offloaded to a computer via cable or wirelessly. Another option is to have a flash card reader permanently connected to your computer: you simply eject the card from the camera and put it into the reader instead of having to plug the camera in.

The future of hard drives may be hybrid hard drives. Hybrid hard drives combine a magnetic hard disk and flash memory into one device. This allows computers to boot, or start, more quickly, and also reduces power consumption.

IV. Find words or phrases in the text with the following meanings:

1. permanent; able to hold data without power;

2. able to be rewritten many times;

3. different sections of a disk drive or storage area;

4. to make a copy of a file so that the original is not lost transferred to another device;

5. a peripheral device that reads and writes flash cards;

6. a product that integrates two different technologies.

V. Listen to a salesperson at his stand at a consumer electronics show describing two flash products to a potential customer. Which product (a or b) is the visitor most interested in?

A The Dragon flash drive

B The Dragon MP4 player

VI. Listen again and tick which features the salesperson mentions for each device.

Features	Dragon flash drive	Dragon MP4 player
Back up computer data Transport files between PCs Audio and video playback FM radio tuner Voice recorder Games

VII. Answer these questions:

1. What is the storage capacity of the Dragon flash drive?

2. How do you connect it to the computer?

3. According to the salesperson, what are the advantages of a USB flash drive over a DVD or a external hard drive?

4. Some portable media players are also known as MP4 players. Why?

5. What is the screen size of the Dragon MP4 player?

6. How long does the battery last?

VIII. In pairs, choose a flash-based device that you own and describe it. The features and questions from listening text will help you. Use the following language patterns:

It has a storage capacity of …

It features … and

It supports multiple formats: … and ….

You can …and…..

Its battery life is …..

Student independent study:

Memory

I. Read the text and make the plan.

It is interesting to note that memory, one of the basic components of the computer, is often called storage. It stores calculation program, the calculation formulae, initial data, intermediate and final results. Therefore, the functions of the computer memory may be classified in the following way. Firstly, the computer memory must store the information transmitted from the input and other devices. Secondly, memory should produce the information needed for the computation process to all other devices of the computer.

Generally, memory consists of two main parts called the main, primary or internal, memory and the secondary or external memory. The advantage of the primary memory is an extremely high speed. The secondary memory has a comparatively low speed, but it is capable of storing far greater amount of information than the main memory. The primary storage takes a direct part in the computational process. The secondary storage provides the information necessary for a single step in the sequence of computation steps.

The most important performance characteristics of a storage unit are speed, capacity and reliability. Its speed is measured in cycle time. Its capacity is measured by the number of machine words or binary digits. Its reliability is measured by the number of failures per unit of time.

План в питальній формі.

1. What is memory?

2. What is the function of memory?

3. What are the main parts of memory?

4. What are advantages and disadvantages of a storage unit?

5. What are their functions?

6. What are performance characteristics of the main and secondary memory?

7. What units are performance characteristics measured by?

План в називній формі.

1. The definition of memory.

2. The main functions of memory.

3. Classification of memory.

4. Advantages and disadvantages of memory components.

5. The functions of memory components.

6. Performance characteristics of memory.

7. The units for measuring the performance characteristics of memory.

План в тезисній формі.

Memory is one of the basic components of the computer.

Memory stores initial data, intermediate and final results.

It produces the information needed to other devices of the computer.

Memory consists of the main (internal) and the secondary (external) storage.

The main memory has high speed, but small capacity; the secondary memory possesses lower speed but greater capacity.

The main memory performs computation; the secondary memory provides information sequentially, step by step.

The performance characteristics — speed, capacity and reliability — are measured by cycles, binary digits and the number of failures per unit of time.

Magnetic storage devices