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

Software engineering, specialization,ggeneralization and aggregation of rai...

specialization,ggeneralization and aggregation of railway reservation system?

Define master construct in fortan, Q. Define Master Construct in FORTAN? ...

Q. Define Master Construct in FORTAN? The master directive has following general form:  #pragma omp master structured_block  It causes master thread to execute structu

List all seven layer of osi model, List all seven layer of OSI model and de...

List all seven layer of OSI model and describe function of application layer. The layers of OSI model are as follows: (1) The Physical Layer: It defines an interface in

We define our own match code id''s for sap matchcodes, Can we define our ow...

Can we define our own Match Code ID's for SAP Matchcodes? Yes, the number 0 to 9 are reserved for us to make our own Match Code Ids for a SAP described Matchcode object.

What is open database connectivity, What is Open Database Connectivity (ODB...

What is Open Database Connectivity (ODBC) It happens that in addition to conventional or most popular database management systems, many companies go for proprietary software c

Explain the difference between ram and rom, RAM: Read / Write memory, High ...

RAM: Read / Write memory, High Speed, Volatile Memory. ROM: Read only memory, Low Speed, Non Voliate Memory.   RAM- Random Access memory it is a Volatile Memory.  volatil

Disadvantages of stateful multi-layer inspection, Disadvantages of Stateful...

Disadvantages of Stateful Multi-Layer Inspection A firewall such as the SMLI remains completely transparent to both users and applications. Consequently, SMLI firewall does no

State a simple pull transaction, a. Explain the future of mobile commerce i...

a. Explain the future of mobile commerce in world? b. 'Push and Pull' are two ways of transferring information to and from a phone, through WAP. Now, with the help of diagram, s

Why do we need registers, Why do we need Registers? If t cpu is cycle...

Why do we need Registers? If t cpu is cycle time of CPU which is the time taken by CPU to execute a well-defined micro-operation employing registers and t mem is memory cycl

Signed 1’s complement representation, Q. Signed 1s complement representatio...

Q. Signed 1s complement representation? Another possibility that is also simple is use of signed 1's complement. Signed 1's complement has a principal. Add both numbers includi

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