which of the following is not a common integrated i/o port? course hero

What are the most important I/O ports on a computer?

Although the most important I/O port on recent systems is the USB port, you might also encounter other ports, including legacy ports such as serial and parallel, which we speak to in this section as well.

What are the types of I/O ports?

Understanding I/O Ports 1 USB 2 Serial (COM) 3 Parallel (LPT) 4 SCSI 5 IEEE 1394 (FireWire) 6 PS/2 (Mini-DIN) 7 Centronics 8 1/8-Inch Audio Mini-Jack 9 SPDIF Digital Audio 10 MIDI Port 11 RG-6 Coaxial

What is an I/O port on a motherboard?

I/O Ports An I/O port is usually used as a technical term for a specific address on the x86's IO bus. This bus provides communication with devices in a fixed order and size, and was used as an alternative to memory access.

What is Input/Output (I/O) devices?

Input/output (I/O) devices enable us to control the computer and display information in a variety of ways. There are a plethora of ports that connect these devices to the computer, for example, the well-known USB port.

What is the IRQ number of a keyboard controller?

For example, the keyboard controller chip is always assigned IRQ 1. A PS/2 mouse is always assigned IRQ 12. The standard IRQ numbers range between 0 and 15. Some are reserved for future use by the owner of the computer; this helps with expansion and adding devices to the system.

What is USB 2.0?

When a USB root hub is enabled in a computer running Windows, two devices are visible in the Windows Device Manager: a USB root hub and a PCI-to-USB universal host controller (USB 1.1) or advanced host controller (USB 2.0), which uses the single IRQ and I/O port address required by USB hardware.

How does a USB hub work?

A bus-powered hub distributes both USB signals and power via the USB bus to other devices. Different USB devices use different amounts of power, and some devices require more power than others do. A bus-powered hub provides no more than 100 milliamps (mA) of power to each device connected to it.

What are the two hardware resources required for serial ports?

Serial ports require two hardware resources: IRQ and I/O port address . Table 3-1 lists the standard IRQ and I/O port addresses used for COM ports 1–4. Some systems and add-on cards enable alternative IRQs to be used, either through jumper blocks (older cards) or via software/Device Manager configuration (newer cards).

What is an IRQ number?

An IRQ is an Interrupt ReQuest, the act of a device interrupting the CPU in order to gain its attention in an effort to send data. This is done by way of an interrupt input line (an actual circuit). The devices, or ports and their associated controlling chips, are assigned IRQ numbers which help the CPU and interrupt controller to differentiate between devices. For example, the keyboard controller chip is always assigned IRQ 1. A PS/2 mouse is always assigned IRQ 12. The standard IRQ numbers range between 0 and 15. Some are reserved for future use by the owner of the computer; this helps with expansion and adding devices to the system.

How fast is a USB 1.1 port?

USB 1.1 ports run at a top speed (full-speed USB) of 12 megabits per second (Mbps), low-speed USB devices such as a mouse or a keyboard run at 1.5Mbps, and USB 2.0 (Hi-Speed USB) ports run at a top speed of 480Mbps.

How does a null modem cable work?

A null-modem cable enables two computers to communicate directly with each other by crossing the receive and transmit wires (meaning that two computers can send and receive data, much like a computer network, though much slower). The best known of these programs is LapLink, but the Windows Direct Cable Connection/Direct Serial Connection utilities can also use this type of cable. Although these programs support serial cable transfers, parallel port transfers are much faster and USB transfers are much faster than parallel; these methods for direct connection are recommended for most versions of Windows. However, Windows NT 4.0 and earlier do not support using the parallel port for file transfers, so you must use a null-modem cable, such as the one shown in Figure 3-7.

What are standardized I/O ports?

As an operating system developer, you should not be looking for this. "Standardized" I/O ports are only used in some situations, such as hardware that was present on pre-PCI (AT and compatible, etc.) PC hardware. Examples of devices using "standardized" I/O ports are the floppy drive, serial and parallel ports, However, most ports are claimed by plugin cards [which?] you might not have and some [which?] are even assigned via PNP which means that any port could be used for the device in question. If you want access to a device, you will need to look up the details for the device in question, and if some fixed port is involved, it will tell you. It is not technically feasible to have a complete mapping of ports to devices as you won't get access to it.

What is an I/O port?

An I/O port is usually used as a technical term for a specific address on the x86's IO bus. This bus provides communication with devices in a fixed order and size, and was used as an alternative to memory access. On many other architectures, there is no predefined bus for such communication and all communication with hardware is done via memory-mapped IO. This also increasingly happens on modern x86 hardware.

Can you map ports to devices?

If you want access to a device, you will need to look up the details for the device in question, and if some fixed port is involved, it will tell you. It is not technically feasible to have a complete mapping of ports to devices as you won't get access to it.

Can a controller listen to legacy ports?

Modern implementations of old devices (typically IDE and VGA controllers) have an implementation that is mentioned to be plug-and-play with moving registers, but they are still able to listen to legacy ports and respond accordingly.