**2. Embedded system versus general-purpose system**

An embedded system is usually classified as a system that has a set of predefined, specific functions to be performed and in which the resources are constrained (Stepner et al., 1999). For example, the mobile phone is an embedded system and it has several readily apparent functions as follows: the main function is to call and receive phone calls, along with perhaps several other functions such as a stopwatch, time-keeper, alarm, and camera and so on. A mobile phone also has several resource constraints as follows: firstly, the processor that is

Potential of Grid Technology for Embedded Systems and Applications 327

5. Embedded systems have real-time constraints. Real-time constraints generally are grouped into categories depending on the application as follows: the first category is time-sensitive constraints and; the second category is time-critical constraints. If the application has time-critical constraints the task must take place within a set window of

Embedded system development tools have traditionally lagged behind tools for the development of general systems (ChristopherChristopher, 2000). Unlike general systems, the design space for embedded systems is extremely large, so it is difficult to contain all of the facilities to specify, design, and test embedded systems. The number of embedded systems increased rapidly year by year and then the designers of the embedded system face ever-increasing challenges in the design stage. Some of these challenges are listed below:

1. In the traditional design method of the embedded system, the hardware and the software of an embedded system are developed simultaneously, which is a sharp contrast to the general or business system. In the business system development, the hardware on which the software should be executed is available. Usually in the business software development, the software can be tested and modified in the computer. However, in the embedded software design, even the specifications of hardware are generally not completed. Therefore, embedded software cannot test on the actual platform until the completion of the hardware. This will cause the degradations of qualities of embedded software as well as increasing the process time

2. In the traditional development method, design took places early in the development process, and the software designer should wait until late in the process. Then the embedded software is tested in the actual prototype. So, revealing the errors in the embedded software is considered a critical step. Furthermore, the discovery of errors often resulted in production delay as well as the possibility of additional expenses to

3. One of the major challenges in the design process of embedded systems is to accurately predict performance characteristics of the final system implementation in the early

4. The complexity of the embedded system arises due to the combination of more and more functions onto a single system (Woodward and Mosterman, 2007 & Madhukar and Lee, 2008). For example, luxury vehicles produced today contain more than 90 embedded electronic control units (ECU), which execute more than 10 million lines of computer codes that control many different functions in a car (Ming-Shan, 2007). Increase of system complexity may also lead to the increase of a project time and the

5. As aforementioned, the main difference between the conventional computer systems and the embedded computer systems is that the hardware on which the software

the product cost (Woodward and Mosterman, 2007 & Manfred, 2006).

time, controlling the flight worthiness of an aircraft is a good example of this. 6. Embedded systems must operate under different environmental conditions. The embedded systems are everywhere, so the system must be designed to work well in

different environment conditions and in the harsh environment as well.

7. Embedded systems microprocessors often have debugging circuitry.

**3. Challenges of embedded software design** 

(Woodward and Mosterman, 2007).

design stages.

system design cost.

Fig. 1. Examples of embedded system

operating the mobile phone cannot be very large, or else no one would use it. Secondly, the power consumption must be minimal as only a small battery can be contained in a mobile phone. Finally, it must perform its function accurately. Each embedded system design satisfies its own set of functions and constraints. By comparing this example with the general propose computer we can see the differences. In this section, the main differences between both systems are described below:


326 Grid Computing – Technology and Applications, Widespread Coverage and New Horizons

operating the mobile phone cannot be very large, or else no one would use it. Secondly, the power consumption must be minimal as only a small battery can be contained in a mobile phone. Finally, it must perform its function accurately. Each embedded system design satisfies its own set of functions and constraints. By comparing this example with the general propose computer we can see the differences. In this section, the main differences

1. Embedded systems are dedicated to specific tasks, where PCs are general computing platforms. An embedded system is programmed to perform specific tasks. Conversely, a general-purpose computer is able to perform unlimited tasks or one can install any software to do all kinds of tasks such as word processing, data sheet, database

2. Embedded systems are usually cost-sensitive because the embedded system is only part of the whole product. Subsequently, if the cost of the embedded system reduces, one

3. The implication of software failure are much more severe in the embedded systems than the general propose computer. It is considered one of the most difficult technical and commercial environments because many critical systems are controlled by the embedded computer system. These include communication systems, transportation navigation systems, medical systems, and financial systems. Failure or compromise of such a system can have significant consequences including disruption of critical

4. Embedded systems have power constrains. This is not a practically serious constraint for the general-purpose computer system. However, consider an embedded system connected to medical system in the ambulance, so the system must work reliably and for a long time with a set of small batteries. So, it is very important issue to keep the

embedded system running on a minute amount of power (Berger, 2002).

Fig. 1. Examples of embedded system

between both systems are described below:

can potentially reduce the product cost.

management, and others depending on one's purposes.

services, financial loss, and loss of life (Thomas, 2006).

