U.S. gives Iran until March to cooperate with IAEA

The United States set a March deadline on Thursday for Iran to start cooperating in substance with a U.N. nuclear agency investigation, warning Tehran the issue may otherwise be referred to the U.N. Security Council.

The comments by U.S. diplomat Robert Wood to the board of the International Atomic Energy Agency signaled Washington's growing frustration at a lack of progress in the IAEA's inquiry into possible military dimensions to Tehran's nuclear program.

Iran - which was first reported to the U.N. Security Council over its nuclear program by the IAEA's 35-nation board in 2006 and then was hit by U.N. sanctions - rejects suspicions it is on a covert quest for atomic bomb capability.

But its refusal to curb nuclear work with both civilian and military applications, and its lack of openness with the IAEA, have drawn tough Western punitive measures and a threat of pre-emptive military strikes by Israel.

A year ago, the IAEA published a report with a trove of intelligence indicating past, and some possibly continuing, research in Iran that could be relevant for nuclear weapons.

The IAEA has since tried to gain access to Iranian sites, officials and documents it says it needs for the inquiry, but so far without any concrete results in a series of meetings with Iran since January. The two sides will meet again in December.

In his statement, Wood requested IAEA Director-General Yukiya Amano to say in his next quarterly report on Iran, likely due in late February, whether Tehran has taken "any substantive steps" to address the agency's concerns.

"If by March Iran has not begun substantive cooperation with the IAEA, the United States will work with other board members to pursue appropriate board action, and would urge the board to consider reporting this lack of progress to the U.N. Security Council," Wood said, according to a copy of his statement.

"Iran cannot be allowed to indefinitely ignore its obligations ... Iran must act now, in substance," Wood said.

Amano earlier told the board that there had been no progress in his agency's year-long push to clarify concerns about suspected atom bomb research in Iran, but said he would continue his efforts.

EU SEES IRANIAN "PROCRASTINATION"

A simple majority in the IAEA board would be required to refer an issue to the U.N. Security Council, which has imposed four sanctions resolutions on Iran since 2006.

It is unclear whether Russia and China - which have criticized unilateral Western sanctions on Iran - would back any U.S. initiative to report Iran again to the Security Council.

Wood later told reporters he hoped the December talks between the IAEA and Iran would be fruitful. But, he added, "I have my doubts about the sincerity of Iran."

The 27-nation European Union told the board that Iran's "procrastination" was unacceptable. "Iran must act now, in a substantive way, to address the serious and continuing international concerns on its nuclear program," it said.

Iran's ambassador to the IAEA, Ali Asghar Soltanieh, criticised what he called "political noise" and "pressure" from the United States and the EU.

Diplomacy between Iran and the powers - the United States, China, Russia, France, Germany, and Britain - has been deadlocked since a June meeting that ended without success.

Both sides now say they want to resume talks soon, after the re-election of U.S. President Barack Obama, and diplomats expect a new meeting in Istanbul in December or January.

Iran is ready for a "face-saving" negotiated solution to the nuclear dispute, but the West must accept the reality that Tehran would never suspend uranium enrichment, Soltanieh said.

Refined uranium can be used to fuel nuclear energy plants, Iran's stated aim, and also provide bomb material if processed further, which the West suspects is Iran's ultimate aim.

The West wants Iran to suspend enrichment, but Iran is showing no sign of backing down.

Iran "has provocatively snubbed the international community by expanding its enrichment capacity in defiance of multiple United Nations Security Council resolutions," Wood said.

(Editing by Mark Heinrich)

(Source :  dailymirror

N. Korea urges foreigners in South to evacuate

SOUTH KOREA: North Korea said Tuesday the Korean peninsula was headed for “thermo-nuclear” war and advised foreigners in South Korea to consider evacuation, in the latest in a series of apocalyptic threats.
The warning followed a similar evacuation advisory the North gave Friday to foreign embassies in its capital Pyongyang, saying it could not ensure the safety of their personnel if a conflict broke out. “The situation on the Korean Peninsula is inching close to a thermonuclear war,” the North's Asia-Pacific Peace Committee said in a statement carried by the North's official Korean Central News Agency.
Saying it did not want to see foreigners in South Korea “fall victim”, the statement requested all foreign institutions, enterprises and tourists “to take measures for shelter and evacuation in advance for their safety”.
The “thermo-nuclear war” threat has been wielded several times in recent months -- most recently on March 7 -- despite expert opinion that North Korea is nowhere near developing such an advanced nuclear device. Last week's warning to embassies was also largely dismissed as anxiety-stirring rhetoric, with most governments involved making it clear they had no plans to withdraw personnel from their Pyongyang missions.
Tuesday's statement said the risk of nuclear conflict was being heightened daily by the “warmongering US” and its South Korean “puppets” who were intent on invading the North.
Earlier Tuesday, North Korean workers followed Pyongyang's order to boycott the Kaesong joint industrial zone with South Korea, signalling the possible demise of the sole surviving symbol of cross-border reconciliation.

Let us start business activities with the help of supporting services

Following is a part of a dialogue between Dhanapala, a successful entrepreneur, and Akila who is wishing to start a small business.
Akila : Good morning Dhanapala Mudalali ! I too am waiting to start a small business.
Mudalali : How good ! So what type of a business are you going to start?
Akila : I recently found a method of producing low cost bricks with greater strength.
Mudalali : Very good ! How can I help you?
Akila : I have some problems to solve.
Mudalali : What are those problems?
Akila : The big problem to me is I have only a small amount of savings but I need some more money..........
Mudalali : Ah......Banks are there for that. You can borrow money from banks. Not only that, you can
            get     many other facilities too from banks.
Akila : What are they?
Mudalali : How many new methods are there to protect your money and facilitate your transactions?
           I think it's better to go to a bank and get more information from them.
Akila : Oh yes. Even if we start a business investing a large amount of money, we have to face
                numerous risks.
Mudalali : There are a lot of insurance schemes for that. So you don't have to be afraid to start a business.
Akila : But I don’t have even a vehicle to transport materials and to distribute bricks, for myself. 68 For
               free distribution
Mudalali : Do we need our own vehicles to do a business? Now there are various types of vehicles to use
           for any purpose and you can buy a vehicle when your business is progressing.
Akila : Then how can I give information to others about my business?
Mudalali : There are a lot of methods for that. We can give publicity by way of notices and even
                through customers. And also it will be easier if you buy a telephone.
Akila : That’s fine. I have another problem.
Mudalali : What’s that?
Akila : I want to distribute the bricks on time. Therefore, I need a system to store them.
Mudalali : Yes, to do the business properly you need a proper and safe place to store your products.
Akila : Yes, I have suitable space for it.
Mudalali : Now all your problems are solved, aren't they Akila?
Akila : Yes, Now I understand that all these services help us to do a business properly.

According to the above dialogue, you would be able to understand the importance of various supporting services when starting and carrying on a business. Let’s examine more about these supporting services

Introduction
It needs the help of various services to start and carry on a business successfully. Those services are called supporting services or auxiliary services. Banks and financial institutions provide various services to facilitate the business transactions and insurance helps to mitigate business risks. The transportation helps to produce
and distribute the goods and services effectively and communication is important to exchange the information with other parties. The warehousing is another service which helps to produce continuosly and to distribute them on time.

After studing this chapter you will be able to understand the following terms

_Banking activities                                      _ Electronic money
_ Commercial banks                                   _ Non banking institutions
_ Current accounts                                     _ Insurance and assurance
_ Cheques                                                  _ Communication
_ Savings deposits                                      _ Transportation
_ Term deposits/ Fixed deposits                 _ Warehousing
_ Commercial bank loans

Programming Language Translation

We have seen in the previous sections that a computer can execute programs written only in a machine code. Therefore a programme written in any other language has to be translated into machine code by using appropriate language translation software to execute it on the computer. The process of converting a program from one language to another is termed Language Translation. There are three techniques for
language translation:
(1) Assemblers
(2) Compilers
(3) Interpreters

1 Assemblers
Assemblers translate assembly language into machine language which can be
recognized by the computer.

2. Compilers
Compilers translate all the commands in a program to an object code which can be understand by the computer. Once a program is compiled, it can be executed by the machine. C and FORTRAN are two
examples of compiler based programming languages.
   When compiling programs, the original program used for the compilation is called the Source Code Program and the resulting program produced by the compiler is called the Object Code Program. The main process what the compiler does is to translate Source Code Program into Object Code Program. During the compilation process, the compiler also checks whether the source program is free of errors with respect to the grammar of the programming language. If the compiler detects errors, error messages are produced and the compilation process terminates without producing the object code. Then the user must compile the program again after correcting the detected errors. The user may have to follow this procedure repeatedly until the program is free of errors. Errors found in a program are called ‘Bugs’ and the process of
eliminating bugs from a program is called Debugging.

3. Interpreters
Unlike compilers, interpreters do not translate the entire program into machine code at once. Instead, an interpreter does the translation at the moment the program is run, one line at a time. As a result, the lines of the program have to be translated into machine code each time the program is run. Therefore, the time taken
to run a program of this type is typically greater than the time taken to run a similar program that has been compiled. ‘VB’ and ‘Python’ are examples of such languages.

Evolution of Programming Languages

All programming languages developed from the inception can be classified into four classes based on the nature of their commands.

1' First Generation Programming Languages
(Machine Languages)

2' Second Generation Programming Languages
(Assembly Languages)

3' Third Generation Programming Languages
(High Level Languages)

4' Fourth Generation Programming Languages
(Artificial Languages)

One of the key features apparent in the evolution of programming languages is that the programming languages have become easily understandable and usable over the years.

First Generation Programming Languages
All machine languages fall into this category.
Common Properties of these languages:

•  All commands are based on the binary code symbols 0 and 1.
• Coding programs and programming computers are extremely difficult.
• Depend on the machine type. Therefore, a program coded for one processor type may not run on a machine with a different processor type.
• Programmer should have a comprehensive knowledge about the hardware of the intended computer system.

Second Generation Programming Languages
These languages were developed primarily to alleviate the problem of using
only the binary symbols 0 and 1 to develop programs.
Common Properties of these languages:

•  Commands are represented by symbolic names such as ‘ADD’,SUB’.
•  Ability to use symbolic names to store data at memory locations and to retrieve data from memory by using these symbolic names.
• Ability to debug programs easier than programs in machine code.
•  Depend on the machine type.
• Need for Programmer to have comprehensive knowledge of hardware of the intended computer system.

Programs written in Assembly Languages cannot be executed directly on the computer as Assembly Languages are not understood by the processors. Instead, such programs have to be transformed into the machine language of the intended computer using appropriate language translation software. Such language translation software that translate programs written in Assembly Languages to Machine Language are called ‘Assemblers’.

Third Generation Programming Languages
Programming languages such as C and VB belong to this type.
Common Properties of these languages:

•  Based on languages close to humans such as English .
•  Do not depend on the machine.
•  Programs can be developed and debugged easily.

Like the Assembly languages, these languages also cannot be directly understood by the machines. Therefore to execute programs written in these languages they have to be translated into machine code using
appropriate language translation software.

Fourth Generation Programming Languages
Fourth Generation Programming Languages provide Visual Environment
making it easy for the user to write computer programs.
Common Properties of these languages:

• Close to human languages such as English.
•  Ability to learn the languages within a short period.
•  Ability to accomplish a task by using a smaller number of commands relative to Third Generation Programming Languages.

Mobile Processor Packaging

The heat that processors generate has been a concern since the first computer chips were released. In desktop systems, the heat problem is addressed to a great extent by computer case manufacturers. Multiple cooling fans and better internal layout designs can keep air flowing through the system to cool the processor, which is usually equipped with its own fan and heatsink.

For developers of portable systems, however, not as much can be accomplished with the case arrangement. So, it was up to the chip manufacturers to address the problem in the design and packaging of the chip. Although most portable systems use special mobile processors designed specifically for mobile use, some systems use desktop processors for lower cost, at the expense of battery life and heat generation.

Note

Some manufacturers of portable systems use standard desktop processors. Apart from a greatly diminished battery life, systems such as these can sometimes be too hot to touch comfortably. For this reason, before purchasing a portable system, you should determine whether it uses a mobile or desktop processor and understand the ramifications of each.

Most mobile processors include a built-in thermal diode that can be used to monitor CPU temperature. The laptop systems use this to control fan operation and also for processor performance control. Utilities are available that can use this sensor to display the processor temperature information onscreen.

Tape Carrier Packaging

An early solution to the size and heat problems for processors was the tape carrier package (TCP), a method of packaging processors for use in portable systems that reduces the size of the chip, its power consumed, and its heat generated. A Pentium mounted on a motherboard using TCP is much smaller and lighter than the standard staggered pin grid array (SPGA) that Pentiums used in desktop systems. The 49mm square of the SPGA is reduced to 29mm in the TCP processor, the thickness is reduced to approximately 1mm, and the weight is reduced from 55 grams to less than 1 gram.

Instead of using metal pins inserted into a socket on the motherboard, a TCP processor is essentially a raw die encased in an oversize piece of polyamide film. The film is similar to photographic film. The die is attached to the film using a process called tape automated bonding (TAB), the same process used to connect electrical connections to LCD panels. The film, called the tape, is laminated with copper foil that is etched to form the leads that connect the processor to the motherboard. This is similar to the way electrical connections are photographically etched onto a printed circuit board.

After the leads are formed, they are plated with gold to allow bonding to a gold bump on the silicon die and to guard against corrosion. Next, they are bonded to the processor chip itself, and then the whole package is coated with a protective polyamide siloxane resin and mounted on a filmstrip reel for machine assembly. To get a feel for the small size of this processor, look at Figure 4.1, where it is shown next to a standard-size push-pin for comparison.

Figure 4.1. Pentium MMX processor in TCP Mobile Package. (Photograph used by permission of Intel Corporation.)

Reels of TCP chips are loaded into special machines that stamp-solder them directly to the portable system's motherboard. As such, the installation is permanent; a TCP processor can never be removed from the board for repair or upgrade. Because no heatsink or physical container is directly attached to the processor, the motherboard itself becomes the conduit to a heatsink mounted underneath it, thus using the portable system's chassis to pull heat away. Some faster portable systems include thermostatically controlled fans to further aid in heat removal. Mounting the TCP to the system circuit board requires specific tooling available from all major board assembly equipment vendors. A special tool cuts the tape containing the processor to the proper size and folds the ends containing the leads into a modified gull-wing shape that contacts the circuit board, leaving the processor suspended just above the board. Another tool dispenses a thermally conductive paste to the circuit board before the tape containing the processor is placed. This is done so that the heat can be dissipated through a sink on the underside of the motherboard while it is kept away from the soldered connections. Finally, a hot bar soldering tool connects the leads on the tape to the circuit board. The completed TCP assembly forms an efficient thermal contact directly from the die to the motherboard, enabling the processor to run within its temperature limits even in such a raw state. Eliminating the package and essentially bonding the die directly to the motherboard save a significant amount of size and weight.  Intel Mobile Pentium tape carrier package pinout

Processor Performance Technology - 2

Reducing processor speed and voltage conserves power and dramatically increases battery life, but it also significantly reduces processor performance. This means that applications that require extremely high performance could suffer when in a battery-optimized mode. Additionally, when the processor speed changes, access to memory is temporarily blocked. This can cause problems with applications that require streaming access to memory (such as video playback), resulting in glitches or dropouts in the display. If you want maximum performance when running under battery power, you can manually override or disable the performance control technology.

To disable processor performance-control technology and force the processor to run at maximum performance, if you are running Windows 9x/Me or NT/2000, you should use the application supplied by your laptop manufacturer to disable the technology. If you are using Windows XP, you should select the Always On power scheme, which can be accomplished using the following steps:

1.	Select Start, Control Panel (make sure you're using the Control Panel classic view).
2.	Double-click the Power Options tool and select the Power Schemes tab.
3.	Under Power Schemes, select the Always On scheme.

As you can see from the previous tables, the Always On power scheme in Windows XP automatically selects processor policies of None for both AC and battery power, which means that the processor will be forced to run its highest performance level at all times.

Caution

If you use the Always On power scheme on a laptop, battery life will be greatly reduced, and the system might be prone to run extremely hot or even to overheat. If you find that the system is running too hot when using AC power, you can try selecting a power scheme such as Minimal Power Management or Portable/Laptop, which uses the Adaptive processor policy to reduce power under periods of lower demand. For minimum heat production and maximum battery life, you can try the Presentation or Max Battery schemes.

Processor Performance Technology

Overall, power consumption is one of the biggest issues faced when designing mobile processors and systems. Most laptops are designed to run off battery power when disconnected from an AC power source. The less power required, the longer the system can run between recharges. In this case, battery life is not so much how many times you can discharge and recharge (expressed as the total number of cycles), but how long each cycle lasts. The less power the system requires, the greater the time you can run off an existing charge. Conserving power when connected to AC can also be useful for reducing component temperatures and heat generation in a laptop.

The Mobile Pentium III/Celeron, Pentium 4, Pentium M, AMD K6-2P, AMD K6-IIIP, AMD K6-III+, AMD Mobile Athlon 4, AMD Mobile Duron, AMD Mobile Athlon 64, AMD Mobile Sempron, and AMD Turion 64, as well as the Transmeta processors all feature processor performance-control technology to allow for longer battery life in mobile operation, as well as reduced thermal generation when under AC power. Intel calls this technology SpeedStep (originally code-named Geyserville), AMD calls it PowerNow!, and Transmeta calls it LongRun. This technology enables these processors to optionally reduce both speed and voltage when running on batteries. Earlier processors could reduce speed using SL technology, but by also reducing voltage, the overall power consumption (and heat production) is significantly reduced as well. More recent versions of this technology allow modes to be dynamically switched based on processor demand, not just by whether the system is running on battery or AC power.

Although processor performance-control technology is mainly designed to work when the laptop is running on battery power, it can also be used dynamically when under AC power to help reduce CPU temperature and energy consumption. When the laptop computer is connected to the AC outlet, CPU speed and voltage are normally at or near their maximum. When powered by a battery, the processor automatically drops to a lower frequency (by changing ratios, the bus frequency remains constant) and voltage, thus conserving battery life while still maintaining a relatively high level of performance. In most cases, the actual power consumption drops by half, which means about double the battery life as compared to full power, while reducing speed by only a small amount. For example, a 3.06GHz Mobile Pentium 4 consumes up to 101.4W at full power (3.06GHz and 1.55V), whereas in SpeedStep mode, the power consumption drops to only 40.9W (1.6GHz and 1.2V). This means that although power consumption drops by nearly 60%, the speed drops by only about 48%.

When the system is first powered up, the processor starts in the lower of its two speeds; that is, it starts in Battery Optimized mode. From there, BIOS, driver, or operating system instructions can rapidly switch the processor from mode to mode.

The requirements for this technology to work are as follows:

• A processor that supports SpeedStep/PowerNow!/LongRun technology
• A supporting motherboard (chipset, BIOS, and voltage regulator)
• A supporting operating system (Windows 9x/Me, Windows NT/2000/XP)
• SpeedStep/PowerNow!/LongRun driver (included with XP)

In general, all laptops that came with processors supporting performance-control technology included all of the other required support as well. Note that although it is possible to upgrade processors in many laptops, you generally cannot install a processor supporting SpeedStep/PowerNow!/LongRun technology into an older system that was originally equipped with a processor that did not support that technology.

Systems running Windows 9x/Me or NT/2000 require a special configuration utility or driver to control the processor performance settings. Because the driver must be configured to the specific laptop motherboard, it is available only from the manufacturer or vendor of a given system. Typically, the driver automatically switches processor performance modes when the power source changes from AC to battery power. Normally, the driver displays an indicator (usually a small flag) in the notification area or system tray of the Windows taskbar indicating in which mode the CPU is currently running. The driver also typically adds a processor performance-control tab to the Power Management tool in the Control Panel. By clicking on the indicator in the system tray, you can switch among Maximum Performance, Automatic (dynamically switchable), or Battery Optimized modes on demand. By using the Control tab added to the Power Management tool, you can select options allowing you to disable the processor performance-control technology, add or remove the icon from the taskbar, and enable or disable audio notification when performance changes.

Windows XP includes native support for processor performance-control technologies such as SpeedStep, PowerNow!, and LongRun, which means that manufacturer-supplied drivers are no longer necessary. This native support also includes an algorithm that dynamically balances system performance and power consumption, based on the current CPU workload and remaining battery life. Windows XP uses four specific processor policies (modes of operation) to control processor performance. The processor policies used by Windows XP are shown in below table in order of power consumption from highest to lowest.

Power Scheme	Processor Policy (AC Power)	Processor Policy (Battery Power)
Always On	None	None
Home/Office Desk	None	Adaptive
Minimal Power Management	Adaptive	Adaptive
Portable/Laptop	Adaptive	Adaptive
Presentation	Adaptive	Degrade
Max Battery	Adaptive	Degrade

Mobile Processor Features

As with most portable system components, the main concern with mobile processors is reducing their size, power usage, and heat generation. This allows them to function in the tight confines of a laptop system without overheating, while allowing the longest possible battery life. Mobile processors usually differ from desktop processors in packaging and power consumption, and they can have special features not found in desktop processors. Some of the special features first debuted in mobile processors are subsequently implemented in desktop processors as well. Features unique to mobile processors are discussed in the following sections.

SL Technology

SL technology and SL architecture are terms that Intel used to describe the first system level (SL) power-management improvements that were specially designed for mobile processors and later incorporated into all desktop processors. This technology was first introduced in the 386SL processor in October 1990 and was the first mobile-specific PC processor on the market. The 386SL was based on the 386SX core (16-bit data bus), with added power-management features that Intel then called SL technology. In November 1992, the 386SL was followed by the 486SL processor, which was essentially a 486DX with the same SL technology included in the 386SL. At first, the 486SL was a unique model. However, starting in June 1993, SL technology was available in all desktop 486 processors and all Pentium processors from 75MHz and faster. Every Intel x86 processor introduced since then, from the Pentium II through the Pentium 4 and beyond, has incorporated SL technology.

SL technology consists of a number of processor features that operate at the system hardware level, independent of the operating system or application software. SL technology includes the following features:

• System Management Mode This dedicated special-purpose interrupt and memory address space implements power management transparent to operating system and applications software.
• I/O Restart An I/O instruction interrupted by a System Management Interrupt (SMI) can automatically be restarted following the execution of the Resume (RSM) instruction.
• Stop Clock This control mechanism provides a fastwake-up Stop Grant state and a slowwake-up Stop Clock state, with the CPU operating at 0MHz.
• AutoHALT powerdown After executing a HALT instruction, the processor issues a normal HALT bus cycle, and the clock input to the processor core is automatically stopped.
• Auto Idle powerdown This allows the processor to reduce the core frequency to the bus frequency when both the core and the bus are idle.

The most important part of SL technology is System Management Mode (SMM), which can control and power up/down components without interfering with other system resources. SMM software executes in a dedicated memory space called System Management RAM (SMRAM), which is invisible to operating system and applications software. The CPU enters SMM upon receiving a System Management Interrupt (SMI), the highest-priority nonmaskable interrupt that the CPU can receive. When an event generates an SMI (for example, accessing a device that is currently powered down), the CPU responds by saving the state of the processor to SMRAM. The CPU then switches into SMM and executes the SMM code (also stored in the SMRAM). When the SMM task is complete (for example, powering on the device that was being accessed), the SMI handler executes a Resume (RSM) instruction, which restores the former state of the processor from the SMRAM.

I/O Restart is one of the SL technology functions used with System Management Mode. For example, if an application executes an I/O instruction that tries to access a disk drive that is powered down for battery savings, a System Management Interrupt occurs, powering up the drive and re-executing the I/O instruction automatically. This is transparent to the operating system and application program, allowing the software to run seamlessly.

SL technology also added special clock controls, including Stop Clock, AutoHALT, and Auto Idle. Stop Clock is an instruction that allows control over the CPU clock frequency. When Stop Clock is enabled, the internal frequency of the CPU can be throttled down as low as 0MHz, causing the CPU to consume only a few milliamps of power. This is also called sleep mode. For further power reductions, the external clock signal can be removed altogether, lowering power consumption to the microamp range. This is also called suspend mode.

AutoHALT is an enhancement to the existing HALT instruction and is related to Stop Clock. When a HALT instruction is executed (which stops the CPU from executing further instructions), the CPU automatically executes the Stop Clock instruction and enters sleep mode.

Auto Idle reduces the clock speed of the CPU from normal (clock multiplied) speed down to the CPU bus speed whenever the processor is idle during memory or I/O operations. For example, when the processor is executing an I/O instruction and waiting for the device to respond, the processor speed is automatically reduced to match the CPU bus speed, resulting in power savings without affecting overall performance.

Laptop Processors

Certainly, one of the most important parts in any computer is the central processing unit, or CPU. The CPU can also be referred to as a microprocessor, or just processor, for short. Several types of processors are used in portable systems from several different companies. Processors for portable systems can be the same as those used in desktop systems, but several processor companies also make special processors specifically optimized for use in portable systems. They are generally referred to as mobile processors. This chapter examines primarily the mobile processors used in laptop/notebook and other portable systems.

Currently, Intel and AMD both manufacture processors designed for either desktop or mobile use, and Transmeta makes a series of processors under the Crusoe and Efficeon names that are exclusively for mobile use. As with desktop systems, the majority of mobile systems use Intel processors, and creating chips designed specifically for mobile systems is a major part of Intel's development effort. Over the years, Intel has introduced many different processors for mobile use. Intel has focused on mobile processors since the 386SL came out October 1990 and since then has dramatically expanded mobile processor technology and features. Today the Pentium M processor and the Centrino mobile platform, which is composed of the Pentium M processor, motherboard chipset, and support for Wi-FI, have the largest market share in laptop computers and have gone through several revisions since their initial introduction in 2003. By comparison, AMD was late in catering specifically to the mobile processor market. AMD's first major mobile-only processors were mobile versions of the K6-2 and K6-III released in 1998. In May 2001, AMD announced a line of mobile Athlon 4 (Palomino) and Duron CPUs. The mobile Athlon XP came in April 2002, and the mobile XP-M processor was introduced in March 2003. In 2004 AMD migrated its Athlon 64 desktop processor to laptop computers and named it the Mobile Athlon 64 processor. Today, AMD has just introduced its Turion 64 mobile processor, which builds on the Mobile Athlon 64 processor and is designed to offer similar performance and battery efficiency as Intel's Centrino platform.

Transmeta has had some success in small form factor designs, but generally its processors have failed to keep pace with the mobile offerings from AMD and Intel. Transmeta's processors can, however, be found in subnotebooks, PDAs, and other portable devices. Intel more or less outclassed Transmeta's processors by introducing the Pentium M processor that had similar power consumption and battery efficiency as Transmeta's processors but offered vastly better performance. Transmeta's Efficeon processor succeeds the Crusoe and is, like the Crusoe processor before it, not actually an x86-based processor like Intel's or AMD's. Instead, it uses a different internal logic, Very Long Instruction Word (VLIW), and uses a software layer to convert data from x86-instructions into code the processor can understand.

Main components of a Computer 2

Output Devices
The devices used to get the computer processed data and information out are considered here. Many devices can be used here too and given in Figure  are someof them.

Central Processing Unit (CPU)

The Central Processing Unit is called the brain of the computer. This consists of three parts:
1. Control Unit (CU)
2. Arithmetic and Logic Unit (ALU)
3. Memory Registers  

Control Unit (CU)
All the controlling of the computer is done by this unit. This controls all the devices of the computer giving the required commands when necessary.

Arithmetic and Logic Unit (ALU)
This unit performs all kinds of arithmetic calculations and logical operations.

Memory Registers
The Memory registers are included in the processing unit and it stores the data which are ready to be sent to the Central Processing Unit for calculations or processing.

Main components of a Computer

The computer consists of four main parts. Those are;
1. Input Devices

2. Output Devices

3. Central Processing Unit

4. Storage Devices

Input Devices
The devices which are used to input necessary data and information to a computer are called Input Devices. Many devices are used to input data. Given in Figure  are some of the commonly used devices.

Computer Architecture

Basic functions of a Computer

Five basic functions done by the computer can be identified as follows:
1. Input or inserting data and instructions

2. Processing

3. Output or retrieving data or information

4. Storing data or information

5. Controlling of devices and functions

Input or inserting data and instruction
Input can be defined as inserting data and instructions needed for a computer
Processing
The process of converting data inserted to the computer to information as required can be defined as processing.
Output or retrieving data or information
Giving the processed data and information to the external forces is done under output.
Storing data or information
Data and information are stored in a way that they can be reused later as
required. This is done under storing.
Controlling
The functions of a computer system and its various devices should be controlled properly. Under controlling the controlling activities done by computer system are considered.

Identifying the Computer

In the previous lesson you were made aware of the ways the computers are used in various means. The computer and its associated hardware are discussed in this article
What is a Computer?
The computer can be defined as an electronic machine which can input and save data and instructions, retrieve and process data which have been saved previously and display the processed data or information on the screen or print them. Accordingly, it can be understood that the computer is an electronic tool which
transforms data into information.
What is a Computer Program?
After studying this lesson, you will gain a clear understanding on:
Ø the main process of the computer
Ø the main parts of the computer
Ø architecture of the computer and its ports
Ø data communication
Ø computer networks
Ø internet
The hardware itself is not sufficient to work with the computer. Computer programes are to be installed in the computer to make it functioning. A computer program is a sequence of instructions written to perform a
specified task for a computer.

Special Features of the Computer
Various machines have been invented by man to transform data into information. Among them, the computer commands a vital role. Many reasons have influenced to gain this important position and given below are some of the main reasons.
Speed
The computer is a machine which operates very fast. A task or calculation which takes a long time to be completed through other means can be completed in a very short period using the computer.
Accuracy
The computer is a machine which operates with a very high rate of accuracy. If there is any error in the operation of the computer, such errors occur due to the errors of the given instructions and data. When preparing a program for the computer, it is a fundamental responsibility of the person who prepares the instructions to ensure the accuracy of it.
Efficiency
As it is a machine a computer which is installed in a suitable environment can be operated in the same speed continuously without any rest for any duration you need. This will not feel monotony, fatigue and loss of concentration as human beings.
Versatility
The ability to engage in a number of tasks is a special feature of the computer. Just after finishing one task, the computer can perform another completely different task with the same efficiency.
Storing and Retrieving
The data and information can be saved in the computer as long as we wish and it can be retrieved instantly when we need them. This is another special feature of a computer.
 No intelligence
Intelligent computers have not been created so far and all computers operate according to the commands or programs given by human beings.
No feelings
A computer is just another machine we use. Computers do not get feelings such as isolation, loneliness and exhaustion. Therefore, we can use computers to get our work done as we wish

System Cleaning - 2

3.1 Rear I/O panel of a PC that has gone uncleaned for six months

  3.2 Front panel of a PC that has gone uncleaned for six months

 Six months without a thorough cleaning has left this system totally clogged with dust and pet hair. The purple LPT port at the upper right is stuffed with dust, as are the USB ports at the left.

The front of the system is no better, as Figure 3-2 shows. Dust and dog hair has collected at every small gap through which air is drawn into the case. And yet, this systemwhich happens to be Robert's den systemdid not appear particularly dirty at first glance. The rear of the system was inaccessible and completely out of view. All of the dust and dog hair shown in Figure 3-2 was also invisible, concealed by a hinged door that closes over the drive bays and power switch area.

Pulling the front bezel from the case reveals the built-in air filter shown in Figure 3-3. At first glance, it doesn't appear too bad. There's some dust accumulation, but the filter appears mostly clear. That's because the filter had accumulated so much dust that when we removed the front bezel the dust fell off in a pile, partially visible at the bottom of Figure 3-3.
 

3-3. Built-in air filter

Routine vacuuming of the case exterior helps keep the dust down, but it's not a complete solution. Every few weeks to every few monthsdepending on how dirty your environment isyou'll need to do a more thorough job. To begin, vacuum the exterior surfaces of the case, if you haven't done so already, and if necessary use Windex, Fantastic, Formula 409, or a similar household cleaning solution to remove grease and other accumulations from the case exterior.

Although you can get by with just a standard vacuum cleaner and a brush or two, it's easier to do the job properly if you have the right tools. Most computer stores sell vacuum attachments intended for use with PCs. These attachments are small enough to get in all the cracks and crevices, and the adapter that you use to connect them to your home vacuum is often designed to cut down the air flow to a level more appropriate for cleaning a PC. (We've used some vacuum cleaners that we actually feared might suck components off the motherboard.)

System Cleaning - 1

Dirt is the main enemy of PCs. Dirt blocks air flow, causing the system to run hotter and less reliably. Dirt acts as thermal insulation, causing components to overheat and thereby shortening their service lives. Dirt causes fans to run faster (and louder) as they attempt to keep the system cool. Dirt worms its way into connectors, increasing electrical resistance and reducing reliability. Dirt corrodes contact surfaces. Dirt is nasty stuff.

Computers become dirty as a natural part of running. Fans suck dust, pet hair, and other contaminants into the case, where they rest on every surface. Even in clean rooms, operating theaters, and other very clean environments, a PC will eventually become dirty. If there's any dust in the air at all, the system fans will suck it in and deposit it inside the case, where it will become a problem sooner or later.

The severity of the problem depends on the environment. Industrial environments are often filthy, so much so that standard PCs are unusable. In a shop-floor environment, we have seen standard PCs become so clogged with dirtliterally in one daythat they stopped running because of overheating. Typical home and office environments are much better, but still surprisingly bad. Pets, carpeting, cigarette smoking, gas or oil heatall of these contribute to dirty PCs.

Routine weekly vacuuming of the case exterior helps, but is not sufficient. Figure 3-1 shows the back I/O panel of a PC that was left running 24 hours a day for 6 months in a typical residential environmentwhich happens to be our homewithout being cleaned other than casual vacuuming of the accessible areas of the case. (Barbara asked Robert to point out that she vacuums thoroughly and dusts every week, but that Robert specifically asked her to make no special effort to clean this system so that he could use it as an illustration.)

Lock Others Out of Your Computer

Of course, the opposite of a password that keeps you out of your system is a password that keeps others out of your system. The BIOS in some PCs may provide no password protection at all, a single password that controls access to BIOS setup and allows the system to boot up, or two passwords—one for access to BIOS setup (a Setup or Supervisor password) and bootup, and the other to control access to booting up only (a User or Boot password). To set a password for your system, look in the setup menus for security settings, as shown in

 BIOS and boot passwords can protect you from hackers

A User or Boot password keeps the system from booting up—a measure of intrusion and system hacking protection. A System or Supervisor password keeps lurkers out of your BIOS settings, and keeps them from changing the User/Boot password.

If you are going to set a User or Boot password, be sure you also set a Setup or Supervisor password so the BIOS settings and boot password cannot be changed and so someone cannot set a Supervisor password to keep you out of the system, requiring you to bypass the BIOS password. Because there is a back door, the only way to prevent attackers from circumventing the password is to use a case that can be locked shut with a key or a locking cable.

Component Safety

By now you should know how to keep yourself, your family, and your pets from being electrocuted, prevent your hair getting caught in the fans in your PC, and eliminate the risks of strangulation from neckties and scarves. But it’s not just your safety that you have to be worried about—you also have to care for the safety of the components that you are going to be handling and that are going to become integral parts of your PC.

Dangers You Can See
Here are some general common-sense rules that you can follow to avoid component troubles

• Don’t drop components. This is the number one cause of component damage.
• Don’t bend or flex components. No matter how sturdy a circuit board looks, it takes very little pressure to crack it or pop off an important component.
• Don’t put components down on top of one another or on metal surfaces.
• Keep components clean and dry.

 The easiest way to accomplish all of the above is to store components in their original packaging until needed. This packaging is designed to protect the components on their trip from the factory where they were made to the store selling them, and it’s usually so good that it can protect the contents from the biggest test of all—snail mail delivery!

TIP

There is a very good chance that you will be buying at least some of the parts for your PC via mail order. Mail order is by far the cheapest way to buy components unless you are really lucky and live nearby to a very good supplier. However, component damage in transit is a real problem. Check all items you receive carefully. What you are looking for are components that arrive well packaged and in an undamaged state. Look for signs of damage, both at the packing stage (improperly packaged items, items packed loose) and for damage in transit (ripped, torn, or crushed packaging, items repackaged by the carrier or foot/tire prints on the package—yes, we’ve seen it all!). If anything looks damaged then either refuse to sign for it, or, if you have to sign for it write
“NOT EXAMINED” clearly next to your name/signature and get in touch with the seller.
If, during the build, you think that you may have damaged a component through dropping it or handling it badly, then make a note of this. Damage caused can be difficult, if not impossible to spot, so if you have problems later on, having information on components that might have been damaged can save you a lot of time and energy in tracking down the fault.