Processor Architecture and MicroProgramming
COSC 410 is an advanced course for Computer Science majors that introduces the student to the concepts invloved in the architecture and design of computer systems. Particular emphasis is put on how information is handled at the sub-instruction level." -Dr. Buterbaugh
D.P.Samantarai The New Era of Embedded Internet
"Today, 90% of the microprocessors shipped are used in embedded systems and an average number of microprocessors found at homes exceed 50. Studies estimate the latter figure to reach 200 in 3 to 4 years. "Embedded Internet", a marriage of embedded systems and Internet technology, are the two highly successful miracle technologies that will be responsible for the increase."
Embedded Microprocessors
Uranus was the first planet and was discovered by William and Caroline Herschel on 13 March 1781. Uranus is the seventh planet from the sun and 2,870,990,000 km from the earth. More than one hundred years later, in 1928, a man named Sir Alexander Fleming discovered penicillin. This mould was found to fight germs that are .00004 inches in length. Both of these discoveries were remarkable in the regard that they exposed newfound objects in the world that previously existed without detection. However, in the current age of technology, people find themselves in a world closely surrounded by machines that they do not know exist but benefit from continuously. Obviously, people are aware of computers and other operational machines that have been around for some time now. But few know the extent to which general purpose machines are present are would be surprised to find out that the device that operates their computer, called a microprocessor, is a device found in other machines like a car, a kitchen appliance, or a stereo. These microprocessors, called �embedded� because of their placement, are not only beneficial because of what they have been able to perform, but also for what they may be able to accomplish in the future. This paper will describe embedded microprocessors by discussing (1) what an embedded microprocessor is, (2) common interaction and common products with embedded microprocessors, (3) trends in design, (4) the future of embedded microprocessors and (5) developers of embedded systems.
What is an embedded microprocessor and what does it do? Generally, an embedded microprocessor is a control device inside appliances like microwave ovens and stereo systems. But this control device is unique in each machine, performing only the operation specific to the product, unlike a computer microprocessor. Likewise, the products do not use standard input and output because people do not directly use them. Instead, they are used to control the complex tasks that are done in modern appliances. Yet in more complex devices, like automobiles and copy machines, there is a level of indirect interaction between the user and the device. More specifically, �embedded microprocessors are computer chips used in devices other than computers to provide added functionality, often in areas of control and monitoring.� The control that these processors provide is recurring but essential. Placing an embedded microprocessor system into a product makes the product smart. It can then be programmed to do things that are too difficult or expensive using conventional technologies such as logic or time switches. They have enabled this unnoticed underlying control in many products.
A person might use 100�s of embedded microprocessors a day. For instance, imagine that someone, over the span of just 3 hours, makes a fruit smoothie in a blender for breakfast, changes the channel on the TV with a remote control, rides the elevator in their apartment building, head to the supermarket, stops at a MAC machine, and calls a friend after shopping. They have then used at least one embedded microprocessor in each other those actions. As the author of Embedded Microprocessor Systems says, �Embedded microprocessor systems are affecting our daily lives at a fast pace, mostly unrecognized by the general public. Most of us are aware of the part they are playing in increasing business efficiency through office applications such as personal computers, printers, and copiers.� Actually, �today, 90% of the microprocessors shipped are used in embedded system and an average number of microprocessors found at homes exceed 50�. Some products that include the systems are the following: cars, fridges, traffic lights, industrial equipment, thermostat, telephone, stereo, infrared sensors, video games. These products are used so often, that Eugene Eric Kim says, �If you consider that a microprocessor and memory are what make a computer a computer, then PCs are only part of the pictures. In fact, according to market-research firm IDC, only 20 percent of all microprocessors made in 1996 were used in PCs; the remaining 80 percent were used in embedded system. If you think about it, this isn�t all that surprising. Stereos, coffee makers, and cars all have microprocessors and memory, and are �computers� in every sense of the word.� Kim goes on to say that even though these are embedded systems, �every computer needs software�, thereby indicating the current trends of enhancing embedded microprocessors that predict the future.
The majority of today�s embedded systems rely on 8-bit microprocessors, but the makers of embedded 32-bit processors are developing trends for �smarter� embedded microprocessors. Developing companies have narrowed the gap between embedded and desktop systems, which allows increased functionality of embedded systems. This current trend in development indicates, �a unique combinations of abilities that offer great potential to advance the state of the art in embedded computing.� With 32-bit processors each of these devices is becoming more �individualistic� by offering more features; features that are based on the habits of the users and the patterns they select when using the device. So today, �we see several hot topics in the embedded world, the most notable being super integration, software, multimedia capabilities, and power consumption.� Probably one of the more interesting topics is the ability of embedded microprocessors to aid in artificial intelligence.
The embedded environment presents unusual challenges to a compiler, but the future of artificial intelligence in embedded system has become an intriguing reality. Embedded systems are characterized by small memories, particular microprocessors, performance sensitive applications, and real-time applications; so software possibilities are limited. But artificial intelligence uses embodied software that performs in ways that resemble human intelligence. Some characteristics of A.I. are that it recognizes patterns, it looks for relationships, it learns from its mistakes, and it solves everyday problems. �We want to imbue in our machines the capabilities that we see in humans,� said Dan Lulich, an A.I. authority, robotic vision expert and creator of Onto Bot, a software program that can read a paragraph or a Web page and correctly assign it to one of thousands of subject categories. In recent years, embedded systems can perform activities such as reading and have taken control of products thereby incorporating features of artificial intelligence.
Another stimulating area in the future of embedded systems is using the Internet on a product with an embedded microprocessor. For example, consider a thermostat. This device in a home is used to gauge temperature but theoretically, it could be an Internet-enabled appliance of the future. The thermostat would be embedded with a smart microprocessor that supports an Internet server connection, a Web browser (and screen) for viewing Web information, software and graphics for programming and displays, and a protocol for communicating with the Internet. Users would be able to program the thermostat to gather information form the Web, such as local weather forecasts, to use in regulating the temperature of the house. In addition, users would be able to contact the thermostat remotely, via the Web, to instruct it to alter its settings. The technology to perform this type of embedded control is the future of embedded system.
Cisco, Wind River System, Sun Microsystems, Integrated Systems, Microware Systems, and QNX Software Systems are among the well-known developers of embedded systems. In December 1998 Microsoft held a �soft� or low-publicity launch of AutoPC, a car stereo with a Windows-based operating system, featuring voice recognition, wireless messaging, and a global positioning system (GPS). Engineers of embedded systems feel confident that the Internet will reach into every home and into every product, thereby connections all aspects of life. And with the fast pace of technological progress, the possibility of this kind of connections is right around the corner.
Conclusively, this age of technology has been based not only on what scientists, developers, and engineers can find or build, but also on what we can build to operate on its own. Moreover, as embedded systems are created to do, what these engineers can build to operate at each users distinct preference. And although the majority of people do not know how these systems work, they will undoubtedly recognize the benefits and differences that artificial intelligence provides as auto makers produce technology to reduce collisions, doctors use life-support technologies that remember frequent patients, or embedded systems monitor or control other real world events.
