Computer composition principle-Reading Notes (7) peripheral devices

Peripheral devices are divided into five categories: input devices, output devices, external storage devices, data communication devices, and process control devices.

Each device works under the control of its own device controller, and the device controller is connected to the host through the I/O interface module and controlled by the host.

 

The function of a peripheral device is to connect a computer with other machines and between the computer and the user.

Basic Components of peripheral devices (disks:

Storage Medium: physical features that store information

Drive Device: used for mobile storage media

Control Circuit: send data to or receive data from the storage media

Disk cache:

To make up for the speed difference between the slow disk and the primary storage.

In disk cache, a basic unit composed of some data blocks is called a cache row. The spatial locality and temporal locality of accessed data are used.

CPU cache is implemented by hardware, and disk cache is completed by software and hardware. Use SRAM or dram.

Disks and tapes are magnetic surface memories, featuring large storage capacity, low bit prices, and permanent storage of record information, but slow access speeds. Therefore, they are used as auxiliary large-capacity memory in computer systems.

Disk Array raid is a large-capacity external storage system consisting of multiple disk storages. It implements parallel data storage, cross-storage, and independent storage, improves I/O performance, and increases storage capacity, is an advanced hard disk architecture.

Computer composition principle-Reading Notes (7) peripheral devices