PC PRO 6.0 4.5 Device Driver Management

Be aware of the following when installing devices:

-Before purchasing or installing the device, verify that the device is compatible with the version of Windows you are running. You can: --Check the product documentation and look for the Certified for Windows logo. --Check the Microsoft Hardware Compatibility List (HCL). --Contact the manufacturer to see if the device is compatible. -Obtain the latest driver before installation. Instead of using the driver included on the installation disc, check the manufacturer's website for the latest driver. -Read the product documentation and follow the instructions for installation. Always follow the manufacturer's instructions for installing and configuring a device. -For USB devices, you will typically install the driver prior to connecting the device. -For internal and non-hot swappable devices, turn off and unplug the system before installing the device. -Windows will automatically configure a device if: --The device is fully plug and play capable. --There are no resource conflicts or other problems. --Windows finds a suitable driver in its driver database. --The driver is signed and from a trusted publisher. -On Windows, unsigned and self-signed drivers must be manually approved. However, you cannot install unsigned drivers on x64 versions of Windows.

Signed drivers are drivers that include a digital signature. The digital signature proves that the driver:

-Comes from the reported publisher. -Has not been altered or modified. -Is compatible with the operating system version

Hot swappable devices are devices that can be added and removed without shutting down the computer (technically speaking, hot plug refers to automatically detecting and configuring devices that are added, while hot swap refers to the ability to both add and remove devices).

-Hot swapping must be supported by the BIOS, the bus type or controller, the device, and the driver/operating system. -USB and FireWire devices are examples of buses and devices designed specifically with hot swap support. -Most newer SATA drives are hot swappable. -When you connect a hot swappable device, Windows automatically detects the device, configures a driver (if one is not already installed), and enables the device. -To remove a hot swappable component, use the Safely Remove Hardware feature to shut down the device before unplugging it from the system.

Newer systems use plug and play to automatically configure the resources each device needs. Be aware of the following about plug and play:

-The device, the BIOS, and the operating system must support plug and play standards. -All new devices and operating systems are plug and play compatible. -Plug and play allows IRQ sharing and ensures that the DMA and I/O resources used by each device are unique. -A legacy device is one that does not support Plug and Play. In older systems, you had to manually configure the resources used by each device. Troubleshooting legacy systems often involved finding and resolving resource conflicts. -Although a plug and play system attempts to assign configuration resources around a legacy device's needs, legacy devices often interfere with a plug and play system's ability to properly assign resources.

A computer assigns system resources to hardware devices, and the computer uses these assignments to communicate with the device. You should be familiar with three categories of system resources:

IRQ, DMA, & I/O Address.

Use Device Manager to view installed devices and their status.

To open Device Manager: -Right-click Start and select Device Manager. -In the search field on the taskbar, type Device Manager. -Press the Windows key + R and type devmgmt.msc. Use the device icon to identify the status of the device: -If the icon for the device is not there, then Windows did not detect the device. Try scanning for new hardware or rebooting the system to detect the device. -A normal icon means the device was configured, the appropriate driver was installed, and the device is working properly. -An icon with a yellow exclamation mark means the device was detected but could not be configured properly. In this case, make sure you have the latest driver for the device. -An icon with a black down-arrow means the device is disabled. To identify the system resources used by a device: -Right-click the device and select Properties. -Select the Resources tab. To view all resources used by the computer: -On the file menu in Device Manager, select View > Resources by type (or Resources by connection). -Alternatively, press the Windows key + R, type Msinfo32.

Windows detects newly installed devices and tries to find and load the driver automatically. Many drivers are

automatically included with the operating system. Some drivers are preinstalled during the operating system installation. Windows will automatically use preinstalled drivers when they match new devices. Windows can search the internet for some drivers. If Windows cannot find a suitable driver, you are prompted to identify alternate locations to search in order to find the correct driver.

A driver is program that enables the operating system to interact with hardware devices. Both Legacy and plug-and-play

devices need drivers to configure and use the device.

DMA (Direct Memory Access) channels are conduits high-speed devices use to bypass the CPU and communicate with RAM directly. Devices such as

hard drives, sound cards, and FireWire cards use DMA channels to increase the speed of data transfers. Devices must have a unique DMA channel.

An unsigned driver is one without a digital signature; a self-signed driver is one that

includes a digital signature, but the identity of the entity that signed the driver cannot be verified. You can install unsigned or self-signed drivers.

Devices use IRQ (Interrupt Request) to interact with the CPU. An IRQ allows a device to

interrupt the CPU and request processing time. All new devices allow the sharing of an IRQ; older (legacy) devices had to be assigned a unique IRQ.

An I/O address (also known as a port address) allows two devices in a computer to send information to each other. When a device wants to send information to another device, it addresses the data to the

receiving I/O port number and sends it out on the system bus. Each device in a computer must have its own I/O address.