Computers are used to control a wide range of systems from simple domestic machines, through games controllers, to entire manufacturing plants. These computers interact directly with hardware devices. Their software must react to events generated by the hardware and, often, issue control signals in response to these events. These signals result in an action, such as the initiation of a phone call, the movement of a character on the screen, the opening of a valve, or the display of the system status. The software in these systems is embedded in system hardware, often in read-only memory, and usually responds, in real time, to events from the system’s environment. By real time, I mean that the software system has a deadline for responding to external events. If this deadline is missed, then the overall hardware-software system will not operate correctly.

Embedded software is very important economically because almost every electrical device now includes software. There are therefore many more embedded software systems than other types of software system. If you look around your house you may have three or four personal computers. But you probably have 20 or 30 embedded systems, such as systems in phones, cookers, microwaves etc

Responsiveness in real time is the critical difference between embedded systems and other software systems, such as information systems, web-based systems, or personal software systems, whose main purpose is data processing. For non-real- time systems, the correctness of a system can be defined by specifying how system inputs map to corresponding outputs that should be produced by the system. In response to an input, a corresponding output should be generated by the system and, often, some data should be stored. For example, if you choose a create command in a patient information system, then the correct system response is to create a new patient record in a database, and to confirm that this has been done. Within reasonable limits, it does not matter how long this takes.

However, in a real-time system, the correctness depends both on the response to an input and the time taken to generate that response. If the system takes too long to respond, then the required response may be ineffective. For example, if embedded software controlling a car braking system is too slow, then an accident may occur because it is impossible to stop the car in time.

(Extraído de: Software Engineering, I. Sommerville, 9th Edition, 2011, pg. 538.)

Read the text below and answer the questions that follow.

Text:

How to get the most enjoyment from your
color TV set


Your new color TV incorporates a host of features designed to give you excellent performance. Besides, this model utilizes a highly sophisticated control microprocessor that can give you unprecedented convenience and control in the areas of picture adjustment, channel tuning, monitor operation, on-screen information, and remote control.

We therefore strongly urge that you read all of these instructions before using yourTV for the first time.

Installation

Antenna

Unless your TV is connected to a cable TV system, or to a centralized antenna system, a good outdoor color TV antenna is recommended for the best performance. However, if you are located in a strong signal area that is free from interference and ghost conditions (multipath), an indoor antenna may be sufficient. The two pole antenna packedwith this set is for your convenience only. It is not capable of providing you with the sharp detail and rich color that this televisionwas designed to display.

Location

Select an area where sunlight or bright indoor illumination will not fall directly on the picture screen. Also, be sure that the location selected allows a free flow of air to and fromthe perforated back cover of the set.

Note

Never remove the back cover of the set. This can expose you to very high voltage and other hazards.

If the set does not operate properly, unplug it and call your dealer or service shop.

(Fonte: Color Television – Operating Instructions.)

WELCOME!

And congratulations on your new purchase. You’re now entitled to an unsurpassed service and a number of benefits as part of the Ericsson warranty and service program. Your Ericsson mobile phone was designed to offer you the ultimate in quality, convenience and performance. And of course, we guarantee it. From now on, as the new owner of an Ericsson mobile phone, you’ll have access to a number of exclusive advantages such as: a vast network of Ericsson service centers; a limited 1 year warranty and service agreement, and a toll-free customer service hotline.

WARRANTY CONDITIONS

Dear Customer,

If your Ericsson product needs warranty service, you should send the product to any company authorized service facility. For information contact the store from which you purchased the product. The product in all cases must be accompanied by the following items: your name, address, telephone number, warranty card, bill of sale bearing the serial number, date of delivery, or reasonable proof of these dates, and a detailed description of the problem.

Our warranty

This warranty is extended by Ericsson Inc. (“The Company”) to the original purchaser for use only. Ericsson warrants this product to be free of defects in material and workmanship at the time of its original purchase and for the subsequent period of one (1) year. All accessories for the product are covered for a period of one (1) year fromthe date of purchase.

What we will do

If, during the period of warranty, this product proves defective under normal use and service due to improper materials or workmanship, the company will repair or replace the defective item with a new or factory rebuilt replacement.

(Taken from Ericsson - One yearWarranty and ServiceAgreement)

By Maria E. Andreu

Texto I

Why Is Spain Really Taking Lionel Messi to Tax Court?

By Jonathan Mahler Sep 27, 2013
So Spain has decided to haul Lionel Messi into court for tax evasion, which strikes me as completely insane on pretty much every level.
You may remember the story from a few months back: The greatest soccer player in the world and his father were accused of setting up
a bunch of shell companies in Belize and Uruguay to avoid paying taxes on royalties and other licensing income.

Messi - who makes an estimated $41 million a year, about half from sponsors - reached a settlement with Spain’s tax authorities earlier
this summer, agreeing to pay the amount he apparently owed, plus interest. The matter was settled, or so it seemed. Messi could go
back to dazzling the world with his athleticism and creativity.
Only it turns out that Spain wasn’t quite done with Messi. His adopted country - Messi is Argentine but became a Spanish citizen in 2005
- is now considering pressing criminal charges against him.
Cracking down on tax-evading footballers has become something of a trend in Europe, where players and clubs have been known to
launder money through “image-rights companies” often set up in tax havens. When you need money - and Europe needs money - go to
the people who have it, or something like that. Over the summer, dozens of Italian soccer clubs were raided as part of an investigation
into a tax-fraud conspiracy. A number of English Premier League clubs were forced last year to pay millions of pounds in back taxes.
No one likes a tax cheat, and there’s little doubt that widespread tax fraud has helped eat away at the social safety net in Spain and
elsewhere, depriving schools, hospitals and other institutions of badly needed funds. But Europe is not going to find the answers to its
financial problems in the pockets of some professional soccer players and clubs.
Messi’s defense, delivered by his father, seems credible enough to me. “He is a footballer and that’s it,” Messi’s father Jorge said of his
soccer-prodigy son. “If there was an error, it was by our financial adviser. He created the company. My mistake was to have trusted the
adviser.” Even if Messi is legally responsible for the intricate tax dodge he is accused of having participated in, it’s pretty hard to believe
that he knew much about it.
More to the point, Lionel Messi is probably Spain’s most valuable global asset. What could possibly motivate the Spanish government to
want to tarnish his reputation, especially after he’s paid off his alleged debt? After four years of Great-Depression level unemployment,
have anxiety and despair curdled into vindictiveness?
Here’s another explanation: Maybe this whole case has less to do with money than it does with history. Maybe it’s no coincidence that
the target of the Spanish government’s weird wrath happens to play for FC Barcelona, which is, after all, "mes que un club." It's a symbol
of Catalan nationalism - and a bitter, longtime rival of Spain’s establishment team, Real Madrid.
Too conspiratorial? Prove it, Spain. Release Cristiano Ronaldo’s tax return.

(Adapted form http://www.bloomberg.com/news/2013-09-27/why-is-spain-really-taking-lionel-messi-to-tax-court-.html)