Input/Output

Computer Organization and Architecture

• Interface to CPU and Memory

• Interface to one or more peripherals

Input/Output Module

Draw an illustration of a generic model of an I/O Module

ADC → I/O Module

An external device connected to an I/O Module

Peripheral Device

Suitable for communicating with the computer user

Human readable

Suitable for communicating with equipment

Machine readable

Suitable for communicating with remote devices such as a terminal, a machine-readable device, or another computer.

Communication

Draw an illustration of a block diagram of an external device

What does IRA stand for?

International Reference Alphabet

Coordinates the flow of traffic between internal resources and external devices

Control and Timing

Involves command decoding, data, status reporting, address recognition

Processor Communication

Involves commands, status information, and data

Device Communication

Performs the needed buffering operation to balance device and memory speeds

Data Buffering

Detects and reports transmission errors

Error detection

Draw an illustration of a block diagram of an I/O Module

One of the techniques for I/O operations, where data are exchanged between the processor and the I/O module

Programmed I/O

One of the techniques for I/O operations, where a processor issues an I/O command, continues to execute other instructions, and is interrupted by the I/O module when the latter has completed its work

Interrupt-driven I/O

One of the techniques for I/O operations, where the I/O module and main memory exchange data directly without processor involvement

Direct Memory Access (DMA)

I/O Technique that has no interrupts

Programmed I/O

the two I/O techniques that uses interrupts

Interrupt-driven I/O & Direct Memory Access (DMA)

one of the four I/O Commands,
used to activate a peripheral and tell it what to do

Control

one of the four I/O Commands,
used to test various status conditions associated with an I/O module and its peripherals

Test

one of the four I/O Commands,

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

Read

one of the four I/O Commands,

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

Write

Draw the flowchart for the Programmed I/O technique

Draw the flowchart for the Interrupt-driven I/O technique

Draw the flowchart for the Direct Memory Access I/O technique

Devices and memory share and address space

Memory-mapped I/O

Separate address spaces

Isolated I/O

Draw the block diagram for Simple Interrupt Processing

Most straightforward approach to the problem. Between the processor and the I/O modules

Multiple interrupt lines

When the processor detects an interrupt, it branches to an interrupt-service routine whose job is to poll each I/O module to determine which module cause the interrupt. Time consuming

Software poll

the interrupt acknowledge line is daisy chained through the modules

daisy chain (hardware poll, vectored)

address of the I/O module or some other unique identifier

Vector

processor uses the vector as a pointer to the appropriate device-service routine, avoiding the need to execute a general interrupt-service routine first

Vectored interrupt

An I/O module must first gain control of the bus before it can raise the interrupt request line

Bus arbitration (vectored)

Draw an illustration of a typical DMA block diagram

Data Count → address register

Data Register ←→ data lines

Address Register → data count

Control Logic

→ Request to DMA

← Acknowledge from DMA

← Interrupt

→ Read

→ Write

Draw an illustration of a single-bus, detached DMA

Draw an illustration of a single-bus, integrated DMA-I/O

Draw an illustration of an I/O bus

8237 DMA

Fly-By DMA Controller

What does DCA stand for?

Direct Cache Access

What chip architecture?

Xeon E5-2600/4600 Chip Architecture

It is transmitted in the form of a sequence of protocol blocks called packets or protocol data units

Network traffic

lowest, or link, level protocol

Ethernet

when was the simplest strategy implemented as a prototype on a number of Intel Xeon processors?

between 2006 and 2010

from the evolution of the I/O function, which order is this?
The CPU directly controls a peripheral device

First (1)

from the evolution of the I/O function, which order is this?

A controller or I/O module is added. The CPU uses programmed I/O without interrupts

Second (2)

from the evolution of the I/O function, which order is this?

Same configuration as in step 2 is used, but now interrupts are employed

Third (3)

from the evolution of the I/O function, which order is this?

The I/O module is given direct access to memory via DMA

Fourth (4)

from the evolution of the I/O function, which order is this?

The I/O module is enhanced to become a processor in its own right, with a specialized instruction set tailored for I/O

Fifth (5)

from the evolution of the I/O function, which order is this?

The I/O module has a local memory of its own and is, in fact, a computer in its own right. With this architecture, a large set of I/O devices can be controlled with minimal CPU involvement

Sixth (6)

It is widely used for peripheral connections

Universal Serial Bus (USB)

Defined a low speed data rate of 1.5 Mbps and a full speed rate of 12 Mbps

USB 1.0

Provides a data rate of 480 Mbps

USB 2.0

Higher speed bus called SuperSpeed in parallel with the USB 2.0 bus

Signaling speed of SuperSpeed is 5 Gbps, but due to signaling overhead the usable data rate is up to 4 Gbps

USB 3.0

Includes a faster transfer mode called SuperSpeed+

USB 3.1

was developed as an alternative to small computer system interface (SCSI) to be used on smaller systems, such as personal computers, workstations, and servers

FireWire Serial Bus

A once common standard for connecting peripheral devices to small and medium-sized computers

Small Computer System Interface (SCSI)

Physical organization is a shared bus, which can support up to ? devices

16 or 32

Most recent and fastest peripheral connection technology to become available for general-purpose use

Thunderbolt

Has become a popular interface for storage area networking and other large storage configurations

InfiniBand

InfiniBand’s first version was released in?

early 2001

High-speed bus system for connecting peripherals of a wide variety of types and speeds

Peripheral Component Interconnect Express (PCI Express)

An interface for disk storage systems. Widely used in desktop computers and in industrial and embedded applications

Serial Advance Technology Attachment (SATA)

Has become essential for supporting personal computers, workstations, servers, and massive data storage devices in organizations large and small

Ethernet

Now connects computers, tablets, smart phones, and other electronic devices such as video cameras TVs and thermostats

Wi-Fi