fetch execute cycle
Download
Skip this Video
Download Presentation
Fetch-Execute cycle

Loading in 2 Seconds...

play fullscreen
1 / 14

Fetch-Execute cycle - PowerPoint PPT Presentation


  • 85 Views
  • Uploaded on

Fetch-Execute cycle. Memory Read operation. Read from memory. PC. Main Memory. 1. MAR. Address bus. Other registers. Data bus. MDR. Control bus. ALU. Control Unit. Clock pulses. The Program Counter (PC) holds the address of the next instruction. Electronic Clock. PC. Main

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Fetch-Execute cycle' - aira


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
memory read operation

Memory Read operation

Read from memory

slide3

PC

Main

Memory

1

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

The Program Counter (PC) holds the address of the next instruction

Electronic

Clock

slide4

PC

Main

Memory

10110111

1

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

The contents of the PC are copied to the Memory Address Register (MAR)

Electronic

Clock

slide5

PC

Main

Memory

1

MAR

Address bus

Other

registers

10110111

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

Memory address to be accessed is placed onto the address bus

Electronic

Clock

slide6

PC

Main

Memory

1

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

>>read>>

Clock pulses

Electronic

Clock

The control bus sends a read signal

slide7

PC

Main

Memory

01010111

1

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

The contents of the memory location are passed along the data bus to the Memory Data Register (MDR)

Clock pulses

Electronic

Clock

slide8

PC

Main

Memory

2

1

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

The PC is incremented ready for the next instruction

Electronic

Clock

memory write operation

Memory Write operation

Write to memory

slide10

PC

Main

Memory

2

MAR

Address bus

Other

registers

Data bus

MDR

1110011

Control bus

ALU

Control

Unit

Clock pulses

Electronic

Clock

Data is placed onto the data bus

slide11

PC

Main

Memory

2

MAR

Address bus

Other

registers

11110010

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

Memory address to be written to is placed onto the address bus

Electronic

Clock

slide12

PC

Main

Memory

2

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

>>write>>

Clock pulses

Electronic

Clock

A ‘write’ signal is sent along the control bus

slide13

PC

Main

Memory

2

MAR

Address bus

Other

registers

Data bus

MDR

10111110

Control bus

ALU

Control

Unit

Clock pulses

Electronic

Clock

The data is transferred to the destination in memory

slide14

PC

Main

Memory

3

2

MAR

Address bus

Other

registers

Data bus

MDR

Control bus

ALU

Control

Unit

Clock pulses

Electronic

Clock

The PC is incremented

ad