Device Management & Device Drivers


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Device Management

A general-purpose computer system consists of CPUs and multiple device controllers that are connected through a common bus.

Each device controller is in-charge of a specific type of device. Depending on the controller, more than one device may be attached. For instance, seven or more devices can be attached to the small computer-systems interface (SCSI) controller.

A SCSI controller, also called a host bus adapter (HBA), is a card or chip that allows a Small Computer System Interface (SCSI) storage device to communicate with the operating system across a SCSI bus.
A small computer systems interface (SCSI) is a standard interface for connecting peripheral devices to a PC. Depending on the standard, generally it can connect up to 16 peripheral devices using a single bus including one host adapter.

A device controller maintains some local buffer storage and a set of special-purpose registers. The device controller is responsible for moving the data between the peripheral devices that it controls and its local buffer storage.

Typically,operating systems have a device driver for each device controller. This device driver understands the device controller and provides the rest of the operating system with a uniform interface to the device.

Device Drivers

An Operating System manages device communication via their respective drivers.

It does the following activities for device management

Keeps tracks of all devices. Program responsible for this task is known as the I/O controller.

Decides which process gets the device when and for how much time.
Allocates the device in the efficient way.

De-allocates devices.

Device Management 

Device driver : More commonly known as a driver, a device driver or hardware driver is a group of files that enable one or more hardware devices to communicate with the computer's operating system. 


Without drivers, the computer would not be able to send and receive data correctly to hardware devices, such as a printer.

“Each device has its own device driver”

Devices usually refer to physical/hardware devices such as computers, laptops, servers, mobile phones and more.

In Windows, device management is also an administrative module that is used for managing or configuring the physical devices, ports and interfaces of a computer or server.

Device management generally performs the following:

Device Detection and Addition
Device Deletion
Device Allocation and
Registration
Detaching and Deregistration

Installing device and component-level drivers and related software
Implementing security measures and processes.
Handles interrupts.
Monitor the status of all devices, including storage drives, printer and other peripherals.
Enforce pre-set policies on which process gets which device for how long.
Deal with the allocation of devices to processes.
Deallocation of devices

Examples of devices:
Printer, Keyboard
Mouse, Monitor,
Scanner, CD-Rom,
USB port, WebCam
Microphone


Device Management & Types:

Dedicated Devices
　　　These devices are assigned to one process at a time
　　　The device released only after completion of process
　　　　Ex: Tape Drives

Shared Devices
　　　　These devices are assigned to more than one process at a time
　　　　Ex: Hard Disk


Virtual Devices
　　These devices are a combination of dedicated and shared devices.
　　Ex: Printer (Spooling-Q)
　　


Conclusion


Device Management is another important function of the operating system. 

Device management is responsible for managing all the hardware devices of the computer system. 

It may also include the management of the storage device as well as the management of all the input and output devices of the computer system.

Comments

  1. Gnana Surya PSeptember 11, 2019 at 10:06 AM

    Sir, I clearly understood the device management works and also know it is the another important function in the os

    ReplyDelete

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