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Digital devices · Inside the computer

Peripherals

Emma is on a video call with her grandparents for Thanksgiving. Her keyboard, webcam, microphone, monitor and headphones all work together, but information moves a different way through each one. Peripherals are the doors of the computer: information comes in through some and goes out through others. Classifying them properly helps you understand what each device you plug in actually does. By the end, you will be able to explain exactly what Emma's call needs.

Input, output or both

A few more cases. A 3D printer takes a design from the computer and builds a physical object, so it is output. A barcode scanner or fingerprint scanner reads something from the real world and sends data to the computer, so it is input. Accessibility devices follow the same rule: a screen reader turns text into speech (output), and voice control or an eye-tracking camera sends the user's commands in (input). A TV used as a second screen only shows the image, so it is output.

Diagram of the flow of information between the computer and the peripherals: input ones send information to the computer, output ones receive it from it and mixed ones do both. computer input keyboard, mouse... output monitor, speakers... mixed: touchscreen (input and output)
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Classify these peripherals as input, output, or input-output (both at the same time): keyboard, monitor, printer, microphone, speakers, touchscreen, webcam. Justify each…

Classify these peripherals as input, output, or input-output (both at the same time): keyboard, monitor, printer, microphone, speakers, touchscreen, webcam. Justify each case with a short sentence.

Solve
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Explain in your own words what an input peripheral is and give two examples that you use; do the same for an output peripheral. Then name a device that you connect to a…

Explain in your own words what an input peripheral is and give two examples that you use; do the same for an output peripheral. Then name a device that you connect to a computer or cell phone and classify it.

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The classroom projector shows the computer screen on the wall: is it an input or output peripheral? The classroom interactive whiteboard, besides displaying images,…

The classroom projector shows the computer screen on the wall: is it an input or output peripheral? The classroom interactive whiteboard, besides displaying images, responds when you touch it with the stylus: what about that one? Explain your reasoning for both answers.

Solve
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Is the hard drive inside the computer tower a peripheral? What about an external hard drive connected via USB? Explain the criteria you use to distinguish an internal…

Is the hard drive inside the computer tower a peripheral? What about an external hard drive connected via USB? Explain the criteria you use to distinguish an internal component from a peripheral.

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A classmate says: "the printer is an input device because you put paper into it." Correct their mistake by explaining what counts as "information" when classifying a…

A classmate says: "the printer is an input device because you put paper into it." Correct their mistake by explaining what counts as "information" when classifying a peripheral, and give a counterexample with another device that you also "put" something physical into.

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Choosing the right peripheral

A computer in the center with four peripherals: headphones and projector receive data from the computer (output), and scanner and microphone send data to it (input). computer headphones listen on your own scanner copy a paper photo microphone so people can hear you projector display on a big scale
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Classify these peripherals as input, output, or input-output, and justify each case: a 3D printer, a scanner, a graphics tablet (without a screen, drawn on while looking…

Classify these peripherals as input, output, or input-output, and justify each case: a 3D printer, a scanner, a graphics tablet (without a screen, drawn on while looking at the monitor), a television used as a second computer screen, and a fingerprint scanner.

You can do it on paper and send a photo with your answer.

Solve
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Which peripheral do you need in each situation? (a) you want to listen to music without disturbing anyone; (b) you want to transfer a paper photo to the computer; (c)…

Which peripheral do you need in each situation? (a) you want to listen to music without disturbing anyone; (b) you want to transfer a paper photo to the computer; (c) you want to be heard on a video call; (d) you want to show your presentation on a large scale to the whole class. Explain what type each one is.

Solve
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You make a video call to your grandparents from your computer. Name all the peripherals involved in the call, classify them as input, output, or input-output, and…

You make a video call to your grandparents from your computer. Name all the peripherals involved in the call, classify them as input, output, or input-output, and explain what you would notice in the conversation if each one failed.

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Peripherals that combine input and output

Touchscreen connected to a computer by a single cable: the touch of the finger travels to the computer as input and the image goes back to the screen as output, which is why it is a mixed peripheral. touchscreen (mixed peripheral) a single connection channel computer input touch position output image on the screen
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The diagram shows a computer with several connected peripherals. The blue arrows carry information to the computer and the green ones carry it away; the touchscreen does…

The diagram shows a computer with several connected peripherals. The blue arrows carry information to the computer and the green ones carry it away; the touchscreen does not have an arrow yet, as shown in the figure.

Touchscreen ? COMPUTER Microphone Keyboard Mouse Monitor Speakers Printer

State what type of peripheral each labeled device is (input or output) by looking at the direction of the arrows. Then decide which arrow or arrows the touchscreen, marked with '?', would need, and explain why.

Solve
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The classroom printer prints documents but also scans photocopies and sends them to the computer. Explain why it is considered an input-output peripheral, just like a…

The classroom printer prints documents but also scans photocopies and sends them to the computer. Explain why it is considered an input-output peripheral, just like a touchscreen, and look for two other devices at home that also combine input and output of information.

Solve
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Lucas has severely reduced mobility in his arms and hands (he cannot press small keys or hold a conventional mouse) and also has low vision. At his high school, he has…

Lucas has severely reduced mobility in his arms and hands (he cannot press small keys or hold a conventional mouse) and also has low vision. At his high school, he has been assigned a standard computer with a traditional keyboard, an optical mouse, and a 21-inch monitor.

  1. a) Analyze the accessibility problems of this workstation: identify what physical barrier Lucas encounters for data input and which one for information output.
  2. b) Design an adapted workstation for him: select at least two alternative input peripherals and one alternative output peripheral that address his specific limitations, justifying how Lucas will interact with each of them without depending on another person's help.
Solve

Ports, drivers and the operating system

How does a peripheral actually talk to the computer? Through a port and a cable (or a wireless link), and the operating system (OS) manages it. The OS is the software that manages the hardware, memory and other software. For each peripheral it uses a driver, a small program that tells the OS how to communicate with that device.

Common ports: USB (keyboard, mouse, flash drive, printer), HDMI (monitor, projector, TV: video and sound out), and the audio jack (headphones and microphone). Wireless devices use Bluetooth instead of a cable.

How do you recognize each port by sight? USB-A is a flat, rectangular opening. USB-C is a small, oval opening that works in either direction. HDMI is a wider, trapezoid-shaped opening (one side is slanted) used for video. Ethernet looks like a wide, square opening, bigger than USB, for a network cable. The audio jack is a small round hole, usually marked with a headphone icon. Look at the shape of the plug and the icon beside the port, then match them.

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The figure shows the rear panel of a computer with four ports labeled with letters, and below it four cards with cables and devices to connect, as shown in the diagram.…

The figure shows the rear panel of a computer with four ports labeled with letters, and below it four cards with cables and devices to connect, as shown in the diagram.

REAR PANEL A B C D USB flash drive HDMI cable Network cable Headphones

Match each card to its port (A, B, C, or D) and explain which peripheral or device you would connect in each case and what for.

Solve
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The Technology department is going to buy 30 new mice for the computer lab. The class representative suggests buying Bluetooth wireless mice because "they are more…

The Technology department is going to buy 30 new mice for the computer lab. The class representative suggests buying Bluetooth wireless mice because "they are more modern, eliminate cable clutter on the desks, and work exactly the same as wired ones." However, the teacher prefers wired USB optical mice.

  1. a) Refute the class representative's argument: explain two technical or operational drawbacks of having 30 wireless mice operating at the same time in the same small classroom.
  2. b) A student is going to compete in a fast-paced action video game tournament where every millisecond counts. Technically justify which type of mouse (wired or wireless) they should choose, analyzing latency (response time) and power reliability.
Solve
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The inkjet printer in the Technology classroom is printing defectively: the pages come out with horizontal white lines cutting through the black text, but the titles and…

The inkjet printer in the Technology classroom is printing defectively: the pages come out with horizontal white lines cutting through the black text, but the titles and logos in red and blue print with complete clarity.

  1. a) Analyze the situation and provide a reasoned dismissal of two common potential causes: could it be due to a faulty USB cable? Could it be that the computer does not have the driver installed? Justify why these faults do not match the symptoms.
  2. b) Formulate the most likely hypothesis about which component of the peripheral is failing (think about the ink cartridges/tanks and the nozzles/printheads).
  3. c) Design a logical three-step procedure to try to solve the problem, ordered from lowest to highest cost or difficulty, before concluding that the printer is broken.
Solve

Summary

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