Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
After going through details of device interfaces next point to be discussed is how the interface can be used to support I/O from devices. Binary information received from an external device is generally stored in memory for later processing. Information transferred from central computer in an external device initiates in memory unit. Data transfer between central computer and I/O devices can be handled in some modes. 3 techniques are possible for I/O operation. These are:
Figure below gives an general idea of these 3 techniques:
Figure: Overview of the three Input/ Output
In programmed I/O, I/O operations are fully controlled by processor. The processor executes a program which initiates, directs and terminate an I/O operation. It needs a little special I/O hardware however is quite time consuming for processor as processor has to wait for slower I/O operations to finish.
With interrupt driven I/O when interface decides that device is ready for data transfer it produces an interrupt request to the computer. Upon detecting external interrupt signal processor stops the task it was processing and branches to a service program to process I/O transfer and then returns to task it was initially performing that result in waiting time by the processor being reduced.
With both interrupt-driven and programmed I/O processor is responsible for extracting data from main memory for output and storing data in main memory during input. What about having a substitute where I/O device may directly store data or retrieve data from memory? This alternative is called direct memory access (DMA). In this mode I/O interface and main memory exchange data directly without involvement of processor.
Figure: Three techniques of I/O
Q. What do you mean by instruction cycle? We have considered the instruction execution in previous section. Now let's consider more about different types of instruction executi
What are base tables of an aggregate object? The tables making up an aggregate object (primary and secondary) are known as aggregate object.
Q. Explain about Batch System? A number of computer systems only did one thing at a time. They had a list of computer system can be dedicated to a single program till its c
Update -task updates are Asynchronous updates.
area under curve
Q. Illustrate Internal Organisation of RAM? The construction displayed in Figure below is made up of one JK flip-flop and 3 AND gates. The two inputs to system are one input bi
Q. Feature of micro-instruction execution? Feature of micro-instruction execution is micro-instruction sequencing which involves address calculation of next micro-instruction.
Gordon Grant, majority shareholder and Chief Executive Officer of Finance-IT Ltd, is determined to be one of the entrepreneurs making money out of the recession. He started the fir
Q Perform Binary Subtraction on following: 1) 1101-1000 2) 111.11-101.1 3) 1101.1-1010.01 Q Perform Binary Multiplication & Division on following: 1) 16*2.75 2) 1
CONTROL SECTION: The control section directs the flow of traffic (operations) and data. Also it maintains order within the computer. The control section chooses one program sta
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd