Illustrate about 8259, Computer Engineering

Assignment Help:

Illustrate about 8259

8259A adds 8 vectored priority encoded interrupts to the microprocessor. We can expand it to 64 interrupt requests by using one master 8259A and 8 slave units. CS and WR should be decoded. Other connections are direct to microprocessor. 

Pins D7 - D0: the bidirectional data connection, IR7 - IR0: Interrupt request, used to request an interrupt and connect to a slave in a system with multiple 8259A.

WR:-Connects to a write strobe signal (upper or lower in a 16 bit system), RD: - Connects to IORC signal, INT: - Connects to INTR pin on the microprocessor from the master and is connected to an IR pin on a slave and INTA: - Connects to INTA pin on the microprocessor.  In a system only master INTA signal is connected A0:- Selects different command words with in the 8259A, CS: - Chip select - enables 8259A for programming and control, SP/EN: - Slave Program (1 for master, 0 for slave)/Enable Buffer (controls data bus transceivers in a large microprocessor based system when in buffered mode) and CAS2-CAS0:- Used as outputs from the master to slaves in cascaded systems. 

 

2064_micro.png

                                                            Figure: 8259 Block Diagram


Related Discussions:- Illustrate about 8259

Program, Write a program to find the area under the curve y = f(x) between ...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can b

What is a macro, What is a macro ? How it is defined ? Preprocessor' is...

What is a macro ? How it is defined ? Preprocessor' is a translation phase that is applied to  source code before the compiler  proper  gets  its  hands on  it.  Generally,  th

Describe briefly how firewalls prevent network, Describe briefly how firewa...

Describe briefly how firewalls prevent network. A firewall is only a program or hardware device which filters the information coming via the Internet connection within your pr

Example of ann - artificial intelligence, Example of ANN - artificial intel...

Example of ANN - artificial intelligence: ANNs look like this:   Notice that the x, w, z and y represent actual valued weights and that every the edges in this graph

What is a disk drive, What is a disk drive? The electro mechanical mech...

What is a disk drive? The electro mechanical mechanism that spins the disk and moves the read/write heads known as disk drive.

Can we use flow logic control key words in abap/4, Can we use flow logic co...

Can we use flow logic control key words in ABAP/4 and vice-versa The flow control  of a dynpro having os a few statements that syntactically ressemble ABAP/4  statements .Thou

Routines which handle dynamic processes, Q. Routines which handle dynamic p...

Q. Routines which handle dynamic processes? number of routines which handle dynamic processes:  int pvm_joingroup( char *group ) Enrolls calling process in a na

Cohesion, Identify the type of cohesion in the following statements: 1. ...

Identify the type of cohesion in the following statements: 1. Compute average daily temperatures at various sites 2. Initialize sums and open files 3. Create new temperature rec

What is ai backgammon, This part looks at Berliner's program, two backprop ...

This part looks at Berliner's program, two backprop versions by Tesauro and a temporal difference process by Tesauro. This latter program is VERY good quality and has found strateg

Real-time systems and control, A group report with no more than three stude...

A group report with no more than three students per group is to be handed in to explain your design procedures and simulation results. Representative graphical system outputs (clea

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd