CompTIA Chapter 10 - Essential Peripherals PDF

**Essential Peripherals chapter 10** **Serial Ports** Techs at times have to support or service older gear, such as installed point-of-sale systems or networking components soldiering on in the background. Many of these old devices connect to computers using serial connections, which use the Recom...

**Essential Peripherals chapter 10** **Serial Ports** Techs at times have to support or service older gear, such as installed point-of-sale systems or networking components soldiering on in the background. Many of these old devices connect to computers using serial connections, which use the Recommended Standard232 (RS232), introduced way back in 1960. A serial port manifests as a 9-pin, D-shell male socket, called a DB9 or an RS232. You won't find serial ports on anything made in the last decade. **Understanding USB** The core of USB is the USB host controller, an integrated circuit normally built into the chipset. The host controller acts as the interface between the system and every USB device that connects to it. Connected to the host controller is a USB root hub, the part of the host controller that makes the physical connection to the USB ports. Every USB root hub is a bus, similar in many ways to an expansion bus. A single host controller supports up to 127 USB devices, though real-life circumstances create sharper limits. A USB host controller is the boss (primary) of any device (secondary) that plugs into that host controller. The host controller sends commands and provides power to USB devices. The host controller is upstream, controlling devices connected downstream to it. The host controller is shared by every device plugged into it, so speed and power are reduced with each new device. **USB Standards and Compatibility** Here\'s an updated overview of USB standards, including their speeds: USB Standards Overview USB Versions, Colors, and Speeds - USB 1.0/1.1: - Color: White connectors - Speed: 1.5 Mbps (Low Speed) / 12 Mbps (Full Speed) [^3^](https://community.microcenter.com/kb/articles/453-overview-of-usb-standards-connections-and-functions) - USB 2.0: - Color: Black connectors - Speed: 480 Mbps (High Speed) [^2^](https://www.techadvisor.com/article/742967/usb-speeds-types-and-features-explained.html) - USB 3.0/3.1 Gen 1/3.2 Gen 1: - Color: Blue connectors - Speed: 5 Gbps (SuperSpeed) ^(https://www.techadvisor.com/article/742967/usb-speeds-types-and-features-explained.html)(https://www.xda-developers.com/usb-standards-explained/)^ - USB 3.1 Gen 2/3.2 Gen 2: - Color: Teal blue connectors (not always color-coded) - Speed: 10 Gbps (SuperSpeed+) ^(https://www.techadvisor.com/article/742967/usb-speeds-types-and-features-explained.html)(https://www.xda-developers.com/usb-standards-explained/)^ - USB 3.2 Gen 2x2: - Color: Usually not color-coded - Speed: 20 Gbps [^3^](https://community.microcenter.com/kb/articles/453-overview-of-usb-standards-connections-and-functions) - USB4: - Color: Usually not color-coded - Speed: Up to 40 Gbps [^3^](https://community.microcenter.com/kb/articles/453-overview-of-usb-standards-connections-and-functions) Connector Types - Type-A: Standard rectangular connector - Type-B: Square-shaped connector - Type-C: Reversible oval-shaped connector - Mini and Micro USB: Smaller connectors for mobile devices Backward Compatibility - USB standards are generally backward compatible - Newer versions work with older devices at the older standard\'s speed - USB-C supports various standards (USB 2.0, 3.2 Gen 1, 3.2 Gen 2) Note: Performance is always limited by the slowest component in the connection. For example, a USB 3.0 device connected to a USB 2.0 port will only achieve USB 2.0 speeds (480 Mbps).  USB endpoints are communication channels within a USB device that allow data transfer between the host (like a computer) and the device (like a printer or USB drive). - **Description:** Used for device management and configuration. - **Direction:** Bidirectional (can send and receive data). - **Default Endpoint Number:** 0. 1. **Isochronous Endpoint** - **Description:** Supports time-sensitive data transmission (e.g., audio and video). - **Direction:** Can be either input or output. - **Characteristics:** Ensures timely delivery but does not guarantee error-free delivery. 2. **Bulk Endpoint** - **Description:** For large, non-time-sensitive data transfers (e.g., file transfers). - **Direction:** Can be either input or output. - **Characteristics:** Guarantees error-free delivery but can vary in transfer speed and timing. 3. **Interrupt Endpoint** - **Description:** Used for devices that need to send small amounts of data quickly and require guaranteed delivery (e.g., keyboards and mice). - **Direction:** Can be either input or output. - **Characteristics:** Polling mechanism ensures timely data delivery with limited data size. **Endpoint Characteristics** - **Endpoint Addressing:** Each endpoint is identified by an endpoint number (0-15) and a direction (IN or OUT). - **Transfer Types:** They can support different transfer types, including Control, Isochronous, Bulk, and Interrupt. - **Buffering:** Each endpoint may have its own buffer to hold data temporarily during transmission. **USB Cables and Connectors** When USB 1.1 was introduced, the standard defined two types of connectors: USB A and USB B. USB A connectors plug upstream toward the host controller (which is why you see them on the PC) and USB B connectors plug downstream into USB devices.The A and B plugs come in sizes: "standard" USB A/USB B, miniUSB A/miniUSB B, and microUSB Here is a concise comparison and overview of Mini USB and Micro USB connectors: **Mini USB** \- **Functions:** Supports both data transfer and power connections, enabling charging and data synchronization. **Micro USB** \- **Functions:** Facilitates data transfer, device synchronization, file transfer, and charging.  The introduction of USB 3.0 required an upgraded USB A connector and new Micro-B connectors, capable of handling the much greater speeds. USB 1.1 and 2.0 cables used four-pin connectors, while USB 3.0/3.1 A and B ports and connectors use nine pins. The USB 3 A connector looks exactly like the older USB A connectors, sneaking the new pins into the same old USB A connector. **USB Type-C** USB Type-C is a versatile and widely-adopted connector and cable standard that provides multiple functionalities, including data transmission, power delivery, and video output. **Key Features** 1\. Reversible Design: One of the most user-friendly aspects of USB Type-C is its reversible connector. It can be plugged in either way, eliminating the frustration of trying to figure out the correct orientation. 2\. **Power Delivery:** USB Type-C supports USB Power Delivery (USB PD), allowing for up to 100 watts (20 volts at 5 amps) of power to be delivered. This enables faster charging of devices, such as laptops, smartphones, and tablets, and supports charging multiple devices simultaneously. 3\. **High-Speed Data Transfer:** USB Type-C supports various USB standards, including USB 3.1 and USB4. This means it can offer data transfer speeds of up to 10 Gbps (USB 3.1) and even 40 Gbps with USB4, significantly enhancing the speed for transferring large files. 4\. **Alternate Modes:** USB Type-C can support alternate modes that allow other protocols to run over the same connector. For example, it can be used to output video signals, such as HDMI or DisplayPort, making it ideal for connecting external displays. 6\. **Compatibility:** While USB Type-C itself is a physical connector, it's essential to ensure compatibility with the specific USB version and device capabilities, as not all USB Type-C ports support the same features (e.g., not all support video output). **Cable length is an important limitation to keep in mind with USB:** - USB 1.1 and USB 2.0 specifications allow for a maximum cable length of 5 meters. - The USB 3.x standards has no maximum cable length. Because USB is a two-way (bidirectional) connection, as the cable grows longer, even a standard, well-shielded, 20-gauge, twisted-pair USB cable suffer from electrical interference. - Stick to cables that are no more than about 2 meters long, except in special circumstances. **USB Hubs** A USB hub is a device that extends a single USB connection to two or more USB ports, almost always directly from one of the USB ports connected to the root hub. Hubs also come in powered and bus-powered versions. If you choose to use a general-purpose USB hub, and you have power-hungry devices like external bus-powered hard drives, use a powered hub. A single USB port only provides 500 milliamps of power, which must be split among all the devices connected to an unpowered hub. This means a single power-hungry device connected to the hub can take all the power for itself, starving the other ports of power. **Troubleshooting USB Issues** USB installation issues may occur when too many devices are connected, particularly if they use incorrect ports or draw excessive power. Built-in OS drivers usually handle basic USB devices like keyboards and mice, but advanced features may require specific drivers from the device manufacturer. **Power Issues:** -If USB devices draw too much power, you may see error codes or experience malfunctioning devices. Disconnect some devices from the hub to resolve it, or install a USB expansion card if more connections are needed. \- Windows offers USB selective suspend to save power by turning off USB power when the computer is shut down. This option is adjustable in the Control Panel under Power Options. \- USB devices might not wake up if they\'re put to sleep to conserve power. If a device disappears from Device Manager, check the hub\'s Properties in the Power Management tab and uncheck \"Allow the computer to turn off this device to save power.\" **SIM** Check out the Chapter 10 Challenge! sim, "USB Speeds," to prepare for questions on the CompTIA A+ 1101 exam. You'll find it here: There are reasons other than circuit failure that can affect all USB ports on a computer, categorized by CompTIA as USB permissions. This refers to USB settings in the UEFI/BIOS. Many BIOS setup programs offer settings that influence USB port operations: 1\. **Enabling/Disabling USB Ports:** A setting allows enabling or disabling all onboard USB ports. This can be useful if the USB controller chip fails but the motherboard still works. In such cases, you can add USB ports via an add-on card, which won\'t be affected by the BIOS settings. 2\. **Backward Compatibility:** USB ports are typically set to support older versions by default. However, some BIOS setups allow disabling backward compatibility, preventing USB 2.0 devices from working in USB 3 ports. If a USB 2.0 device, like a mouse or keyboard, doesn\'t work in a USB 3 port, try using a USB 2.0 port and check USB settings in the BIOS. **Introduction** - Developed by Intel and Apple: Introduced in 2011, Thunderbolt combines data, video, and power in a single connection. **Versions** - **Thunderbolt 1:** - **Speed:** Up to 10 Gbps. - **Video:** DisplayPort 1.1. - **Cable Length**: Up to 3 meters with copper cables. - **Thunderbolt 2:** - **Speed:** 20 Gbps by combining two 10 Gbps channels. - **Video:** Supports dual 4K displays. - **Cable Length**: Up to 3 meters with copper cables. - **Thunderbolt 3:** - **Connector**: USB-C. - **Speed:** Up to 40 Gbps. - **Features:** Supports charging (up to 100W), daisy chaining, multiple 4K displays, or one 5K display. - **Cable Length:** - 0.5 meters for passive 40 Gbps cables. - Up to 2 meters for active cables. - Optical cables up to 60 meters. - **Thunderbolt 4:** - **Speed:** 40 Gbps. - **Compatibility:** Includes USB4, enhanced device compatibility, improved power delivery. - **Cable Length**: Up to 2 meters with passive cables, longer with optical. - **Thunderbolt 5 (announced for 2023):** - **Speed:** Up to 120 Gbps with dynamic bandwidth management. - **Features:** Supports multiple high-resolution displays, enhanced charging (up to 240W). - **Cable Length:** Active or optical cables recommended for longer distances. **Key Features** - **High Bandwidth**: Suitable for high-performance tasks. - **Daisy Chaining**: Connect multiple devices in series. - **Compatibility:** Backward compatible with previous Thunderbolt versions and USB standards. - **Versatility:** Supports data, video output, and charging. **General Port Issues** When troubleshooting a non-working port, start by distinguishing whether the issue lies with the port or the connected device. Test the port by trying a second, known-good device. If the second device also fails, the port is likely the issue. Conversely, test the original device in a different, known-good port. **If you suspect the port isn\'t functioning, consider the following steps:** 1\. **Check if the Port is Enabled:** Ports can often be disabled in the system setup (BIOS/UEFI). Restart the computer and verify if the port is turned off in the setup utility. 2\. **Use Device Manager:** In Windows, you can enable or disable ports via Device Manager. Right-click the device icon associated with the port and select \"Enable\" if it\'s disabled. 3\. **Check for Driver Issues:** Ports, like devices, require drivers. Operating systems usually have built-in drivers for common ports. If the port still doesn\'t appear active despite being enabled, it might have a physical defect.. **Keyboards** In Windows, the primary configuration tool for managing keyboard settings is the Keyboard Control Panel applet. This allows you to adjust: \- **Repeat Delay:** The time you must hold a key before it starts repeating. \- **Repeat Rate:** How quickly the character repeats once it starts. \- **Cursor Blink Rate**: The speed at which the cursor blinks. Some keyboards have additional drivers that provide extra configuration options. **Keyboard Compatibility:** \- **Windows and Linux:** Both use standard QWERTY keyboards with **Ctrl** and **Alt** keys for shortcuts (**like \`Ctrl-Z\` for undo).** \- **Windows Keyboards:** Include a Windows logo key as an additional modifier. \- **Apple Keyboards:** Feature **Control**, **Option**, and **Command** keys, with **Control** and **Option** corresponding to **Ctrl** and **Alt**. The **Command** key serves as the macOS special modifier. Windows keyboards can be used with macOS, but you may need to remap modifier keys in the Keyboard preferences. **KVM Switches** A **KVM (Keyboard, Video, Mouse**) switch is a hardware device that allows users to control multiple computers from a single keyboard, monitor, and mouse setup. This technology is particularly useful in scenarios where space is limited or when managing multiple systems. **Key Features** 1\. **Single Control Point:** A KVM switch provides a centralized control point, enabling users to switch between multiple computers without needing separate peripherals for each system. 2\. **Video Support**: KVM switches support various video resolutions and formats, allowing them to work with different monitors, including HDMI, DisplayPort, VGA, and DVI. 3\. **Multiple Connection Types**: Many KVM switches accommodate various input interfaces, making them compatible with a wide range of devices, from desktops to servers. 4\. **Hotkey Switching:** Most KVM switches offer hotkey functionality, allowing users to switch between connected computers using keyboard shortcuts, enhancing efficiency. 5\. **USB and Audio Support:** Many modern KVM switches support USB connections for peripherals and can also carry audio signals, making it possible to control audio devices connected to the computers. 6\. **Multimedia Functionality**: Some KVM switches come with additional features for multimedia control, such as built-in audio switching or integrated USB hubs. **Installation:** \- When setting up, connect each set of cables between the KVM ports and the computers one at a time, ensuring each keyboard, mouse, and video cable is correctly matched to the intended computer. \- Incorrect connections can prevent the KVM switch from functioning properly, so careful attention to cable management is crucial. A screenshot of a computer Description automatically generated **Video Formats** Video files can be massive, A video is two or more separate tracks---moving picture and audio---that each go through a compression algorithm (codec). The compressed tracks then get wrapped up into a container file, what's often called a wrapper. When you receive a file saved in a standard **wrapper**, such as.MOV for a QuickTime Movie file, you have no way to know for certain which codecs were used to compress the video or audio tracks inside that container file. **Codecs** Video files use standard audio codecs for the audio tracks, such as WAV or MP3, but vary wildly in the type of video codecs used. Just as with audio codecs, video codecs take a video stream and compress it by using various algorithms. Here are some of the standard video codecs: - MPEG-2 Part 2, used for DVDs, broadcast TV. - H.264, used for everything from smartphone video and streaming video to Blu-ray movies. - H.265, half the size of H.264 at the same quality. Used to support 4K video. - VP9, Google's competitor to H.265, used in places like Android devices. - AV1, another competitor to H.265, designed by a group of companies including Amazon, Intel, Microsoft, and Google. YouTube is one its main users. **Wrappers** When both video and audio streams in a video file are compressed, they\'re placed in a container file or wrapper. The key point is that the wrapper doesn\'t specify how the video or audio tracks are encoded. \- **AVI:** A container file for Windows, though not commonly used today. \- **MOV**: The standard format for Apple QuickTime. \- **MP4:** Widely used today, often for H.264 and H.265 video. \- **MKV:** The Matroska Multimedia Container, free and open, with native support in Windows 10 and 11.  **Secure Digital** Secure Digital (SD) cards, as mentioned earlier, are common but becoming less so. **SD cards come in three storage capacities:** - Standard SD Storage: 2GB or less, FAT12 or FAT16. - Secure Digital High Capacity (SDHC) Storage: 2GB to 32 GB, FAT32. - Secure Digital Extended Capacity (SDXC) Storage: 32 GB to 2 TB, exFAT. - Secure Digital Ultra Capacity (SDUC) Storage: 2TB to 128TB, exFAT To help users select SD cards with appropriate performance, several standards indicate their speed capabilities, divided into three generations: **1. Speed Class (First Generation):** Indicates minimum write speeds in megabytes per second (MB/s). \- Class 2, 4, 6, and 10 correspond to minimum write speeds of 2, 4, 6, and 10 MB/s, respectively. **2. UHS Speed Class (Second Generation):** Introduced with the Ultra High Speed (UHS) bus. \- **Class U1:** Minimum read/write speed of 10 MB/s. \- **Class U3:** Minimum read/write speed of 30 MB/s. **3. Video Speed Class (Third Generation):** Supports modern video standards, such as 4K and 8K. \- Classes range from **V6** (6 MB/s) to **V90** (90 MB/s). Modern SD cards may display multiple speed ratings, guaranteeing they can continuously write at the stated rate or higher. This is crucial for devices like video cameras that require sustained write speeds. **A1 and A2 Classes:** \- Both support a minimum of 10 MB/s sustained write speed. \- **A1**: 1500 IOPS for reads and 500 IOPS for writes. \- **A2:** 4000 IOPS for reads and 2000 IOPS for writes, ideal for apps with multiple I/O operations. Maximum read speeds are often indicated on the cards, while write speeds are typically found in product listings. Due to varying quality, SD cards of the same capacity can have different prices and performance levels, so it\'s important to assess each card\'s specifications to ensure compatibility with high-performance devices. **CD-Media** All you're about to read is relevant and fair game for the CompTIA A+ certification exams. CDs store data by using microscopic pits burned into a glass master CD with a powerful laser. Expensive machines create plastic copies of the glass master that are then coated with a reflective metallic coating. CDs store data on one side of the disc only. The CD drive reads the pits and the non-pitted areas (lands) and converts the pattern into ones and zeros. **CD Formats** The first CDs used the CD-Digital Audio (CDDA) format, or CD-audio, with variable-length tracks for music. While great for music, CD-audio lacks error checking, file support, and a directory structure, making it unsuitable for data. Thus, CD-ROM was created, dividing CDs into fixed sectors of 2353 bytes. CD-ROMs use the ISO-9660 file system, known as the CD File System (CDFS), allowing compatibility with non-PC devices and remaining the standard for most data CDs today. **CD-ROM Speeds** The industry sought to increase the speed of CD-ROM drives. Each increase in speed is measured in multiples of the original 150 KBps and is denoted with an \"×\" to indicate the speed relative to the initial (1×) drives. Here's a list of the common CD-ROM speeds, including most of the early speeds that are no longer produced: 1× 150 KBps 24× 3600 KBps 2× 300 KBps 36× 5400 KBps 4× 600 KBps 48× 7200 KBps 16× 2400 KBps 72× 10800 KBps