Раздел 6 Первое занятие

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On the 1980’s new memories technologies involving magnetic bubbles, superconducting tunnel-junction devices and devices accessed by laser beams or electron beams come into play.

Modern computers have significantly more memory than the first PC’s of the early 1980’s, and this has had an effect on development of the PC’s architecture. Storing and retrieving data from a large block of memory is more time consuming than from a small block. With a large amount of memory, the difference in time between a register access and a memory access is very great, and this has resulted in extra layers of “cache” in the storage hierarchy.

When it comes to access speed, processors are currently outstrip­ping⁴⁸ memory chips by an ever-increasing margin (предел рабочего режима). This means that processors are increasingly having to wait for data going in and out of main memory. One solution is to use “cache memory” between the main memory and the processor and use clever electronics to ensure⁴⁹ that the data the processor needs next is already in cache.

Main memory is attached⁵ to the processor via its address and data buses⁵¹. Each bus consists of a number of electrical circuits or bits. The width of the address bus dictates how many different memo­ry locations can be accessed, and the width of the data bus how much information is stored at each location. Every time a bit is added to the width of the address bus, the address range doubles. In 1985, Intel’s 386 processor had a 32-bit address bus, enabling it to access up to 49B of memory. The Pentium processor — introduced in 1993 - increases the data bus width to 64-bits, enabling it to access 8 bytes of data at a time.

In late 2000 IBM and German semiconductor company Infine­on Technologies AG announced plans to collaborate (сотрудничать) in the development of Magnetic Random Access Memory (MRAM) a breakthrough memory technology that could significantly increase battery life of portable computing devices and lead to “instant-on”⁵² computers.

Since MRAM also retains⁵³ information when power is turned off, it means that products like personal computers could start up in­stantly, without waiting for software to “boot up” (загружать). Non- ^volatility also means reduced power consumption. Since it will not need

15 Бух

Микроэлектроника настоящее и будуще*

constant power to keep the data intact^,4. M RAM could consume much less than established random access memory technologies, extending the battery life of cell phones, handheld devices, laptops (портатив­ный компьютер) and other battery-powered products.

By early 2002s, it should be clear whether the technology can be scaled down enough to make it feasible⁵⁵ and whether the magnetic material can be worked into traditional chipmaking processes. If so, it is expected that actual MRAM products could be commercially available as soon as 2004, and that the technology could represent a serious threat to the various silicon-based memory chips towards 2010.

3. Проверьте, как вы запомнили слова.

5. Переведите выделенные слова, исходя из значений, приведенных в скобках:

1. store v (хранить), storage п

2. capacity п (объем, емкость), capacitance п

3. retrieve v (отыскивать), retrieval п

4. overlap v (перекрывать, дублировать), overlapping п

5. call v (вызывать), recall п

6. distinction п (различие), distinct а

7. contrast п (противоположность), by contrast

8. address п (адрес, обращение), addressable а

9. significance п (значение), signify v

10. branching п (ветвление), branch п

11. challenge п (проблема), challenging а

12. succeed v (следовать), succession п

13. intersection п (пересечение), intersect v

14. versatility п (универсальность, эксплуатационная гибкость) versatile а

6. Назовите термин, исходя из следующих определений:

1. storage facilities of the computer

2. a semiconductor device used to store information in the form of electrical charges

3. the amount of time required to move one byte or word of infor­mation into or out of memory

4. a computer that operates on discrete data