Input/Output (I/O) Interfacing

Question 1

a subsystem of components that moves coded data between external devices and a host system, consisting of a CPU and main memory.

Answer 1

Input/Output (I/O)

Question 2

depends upon the size of computer and the peripherals connected to it

Answer 2

I/O Organization

Question 3

An external device attached to the computer by a link to an I/O module

Answer 3

Peripheral Device

Question 4

Common Input/Output devices

Answer 4

Monitor
Keyboard
Mouse
Printer
Magnetic tapes

Question 5

Three categories of external/peripheral device

Answer 5

Human readable
Machine readable
Communication

Question 6

A type of peripheral device suitable for communicating with the computer user

Answer 6

Human readable

Question 7

A type of peripheral device suitable for communicating with equipment, such as sensors and actuators

Answer 7

Machine readable

Question 8

A type of peripheral device suitable for communicating with remote devices such as a terminal, a machine readable device, or another computer.

Answer 8

Communication

Question 9

I/O subsystems

Answer 9

Blocks of main memory
Buses
Control modules
Interfaces to external components
Cabling or communications links

Question 10

exact form and meaning of the signals exchanged between a sender and a receiver

Answer 10

protocol

Question 11

the receiver must acknowledge the commands and data sent to it or indicate that it is ready to receive data. This protocol exchange is called

Answer 11

handshake

Question 12

Signals comprised by protocol

Answer 12

command signals
status signals
data-passing signals

Question 13

serve as interfaces between the CPU and its peripherals

Answer 13

Dedicated I/O modules

Question 14

provides a method for transferring information between internal storage (such as memory and CPU registers) and external I/O devices.

Answer 14

Input – Output Interface

Question 15

special hardware components between the CPU and peripherals to supervise and synchronize all input and out transfers.

Answer 15

Interface Units

Question 16

I/O Module Function that coordinates the flow of traffic between internal resources and external devices.

Answer 16

Control and timing

Question 17

I/O Module Function that involves command decoding data status reporting address recognition.

Answer 17

Processor communication

Question 18

I/O Module Function that detect and reports transmission errors

Answer 18

Error detection

Question 19

I/O Module Function that performs the needed buffering operation to balance device and memory speeds.

Answer 19

Data buffering

Question 20

I/O Module Function that involves commands, status information and data.

Answer 20

Device communication

Question 21

It defines the typical link between the processor and several peripherals.

Answer 21

I/O BUS and Interface Module

Question 22

four types of I/O commands

Answer 22

Control
Test
Read
Write

Question 23

I/O Command that is used to activate a peripheral and tell it what to do

Answer 23

control

Question 24

I/O Command that is used to test various status conditions associated with an I/O module and its peripherals.

Answer 24

test

Question 25

I/O Command that causes the I/O module to take an item of data from the data bus and subsequently transmit that data item to the peripheral.

Answer 25

write

Question 26

I/O Command that causes the I/O module to obtain an item of data from the peripheral and place it in an internal buffer

Answer 26

read

Question 27

the address and data lines from the CPU can be shared between the memory and I/O devices

Answer 27

Shared I/O arrangement

Question 28

Devices and memory share an address space. I/O looks just like memory read and memory write

Answer 28

Memory – Mapped I/O

Question 29

Separate address spaces. Need I/O or memory select lines.

Answer 29

Isolated I/O

Question 30

different I/O techniques

Answer 30

programmed i/o interrupt-driven i/o Direct Memory Access (DMA)

Question 31

refers to data transfers initiated by a CPU under driver software control to access registers or memory on a device. sometimes called polled I/O.

Answer 31

Programmed I/O

Question 32

Instead of the CPU continually asking devices whether they have input, the devices tell the CPU when they have data to send

Answer 32

Interrupt-Driven I/O

Question 33

The circuit that handles interrupt signals from all I/O devices in the system

Answer 33

intermediary interrupt controller

Question 34

recognizes interrupt signals from any of its attached devices, it raises a single interrupt signal that activates a control line on the system bus

Answer 34

Interrupt controller

Question 35

Type of interrupt where the signal for the processor is from external device or hardware

Answer 35

Hardware Interrupt

Question 36

The hardware interrupts which can be delayed when a much highest priority interrupt has occurred to the processor

Answer 36

Maskable Interrupt

Question 37

The hardware which cannot be delayed and should process by the processor immediately

Answer 37

Non Maskable Interrupt

Question 38

It is a software interrupt caused by the software instructions

Answer 38

normal interrupt

Question 39

It is a software interrupt caused by unplanned interrupts while executing a program

Answer 39

exception

Question 40

a special hardware that manages the data transfers and arbitrates access to the system bus.

Answer 40

Direct Memory Access Controller

Question 41

device can transfer data directly to and from memory, rather than using the CPU as an intermediary.

Answer 41

Direct Memory Access

Question 42

DMA controller three registers

Answer 42

address register data count register control logic