Digital Systems - Building the Input/Output System

Flashcards about Input/Output Systems based on lecture notes.

What is the primary function of the input/output (I/O) system?

Enables the attachment of input and output devices to the processor.

Give some examples of input devices.

Keyboards, mice, track balls, touch screens, musical instruments, cameras, environmental sensors.

Give some examples of output devices.

Displays, printers, speakers, environmental actuators.

Give some examples of input-and-output devices.

Network interfaces (Ethernet, WiFi, Bluetooth), disks, audio cards, MIDI devices.

What is the speed-gap challenge in I/O systems?

I/O devices are often mechanical and run slower than the CPU.

How do operating systems handle the diversity of I/O devices?

Operating systems abstract over device diversity using device drivers.

What are device drivers?

Software plug-ins that abstract over device diversity by grouping similar device types.

What are the typical functions of device drivers?

Registering a device, initiating data transfers, monitoring status events, and managing device/system shutdown

What is the difference between character devices and block devices?

Character devices send and receive one byte at a time, while block devices send and receive multi-byte blocks.

Give a classic example of character devices.

Keyboard

Give a classic example of block devices

Hard disk.

How are hard disks addressed at the device level?

What is a common sector (block) size for hard disks?

512 bytes

What are the key characteristics of isolated I/O?

Dedicated physical pins and instructions for I/O operations.

Give an example of Intel x86 instructions used in Isolated I/O.

IN destinationregister, portaddress; OUT sourceregister, portaddress

What is the key characteristic of memory-mapped I/O?

Devices sit within the CPU's linear memory address space.

What is the main distinction between isolated I/O and memory-mapped I/O?

Isolated I/O uses dedicated pins and instructions, while memory-mapped I/O places devices in the CPU's memory address space.