Pin functions of 8086-microprocessor, Assembly Language

Assignment Help:

Pin functions for the minimum mode operation of 8086 are following:

1) M/I/O -Memory/IO: This is a status line logically equivalent to S2 in maximum mode. When it is low, it denotesthe CPU is having an I/O operation, and when it is high, it denotes that the CPU is having a memory operation. In the previous T4this line becomes active and remains active till last T4 of the current cycle. During local bus this is tristated "hold acknowledge".

2) INTA-interrupt Acknowledge: This signal is utilized as a read strobe for interrupt acknowledge cycles.  In other terms, when it goes low, this means that the processor has accepted the interrupt. It is active low during T3, T2 and Tw of each interrupt acknowledge cycle.

3) ALE-Address  Latch  Enable: This  output  signal  indicates  the  availability  of  the  valid  address  on  the address/data lines, and is associated to latch enable input of latches. This signal is active high and is never tristated.

4) DT/R  -Data  Transmit/Receive: This output is utilized to decide the direction of data flow through the transreceivers (bidirectional  buffers). When the processor sends data, this signal is high and when the processor is receiving data, this signal is low. Logically, this is corresponding toS1 inmaximum mode. Its timing is the similar as M/I/O. This is tri stated during 'hold acknowledge'.

5) DEN-Data Enable: This signal denote the availability of valid data over the address/data lines. It is utilized to enable the Trans receivers (bidirectional buffers) to separate the data from the multiplexed address/data signal. It is active from the centre of T2 until the middle of T4.

DEN is tristated during 'hold acknowledge' cycle. HLDA-Hold/Holdand HOLD Acknowledge: When the HOLD line go high, it denote to the processor that another master is requesting the bus access. , in the middle of the next clock cycle after receiving the HOLD request the processor is use the hold acknowledge signal on HLDA pin after completing the current bus (instruction)  cycle. At the same time, the processor floats the control lines andlocal bus. When the processor detects the HOLD line low then it lowers the HLDA signal. HOLD is asynchronous input and it should be synchronized externally.

 


Related Discussions:- Pin functions of 8086-microprocessor

8086 minimum mode system and timing-microprocessor, 8086 Minimum mode Syst...

8086 Minimum mode System and Timing In a minimum mode 8086 system, the microprocessor 8086 is operated in minimum mode by strapping its MN/MX pin to logic 1.All the control si

Assembly HW help, I was wondering if you guys could offer me some advice an...

I was wondering if you guys could offer me some advice and help on how to proceed - not answers- for a homework problem I am attempting. I am currently working on a "bomb" project

#title.Statement of the Problem., Can you write for me an essay, topic is: ...

Can you write for me an essay, topic is: Statement of the Problem. Length: 270 words. I will send you the Formula for the Problem Statement on your Email attachment. Do you agree?

8279 keyword /display controller-microprocessor, 8279 Keyword /Display Cont...

8279 Keyword /Display Controller : Figure shows the structure of 8279 and its interface to the bus. Addressing is according to the table given below. CS        RD

First generation microprocessor, 1 st Generation Microprocessor : At ...

1 st Generation Microprocessor : At the end of the 70s a group of engineers developed a chip is able to processing data. This chip was called processor chip. Big processors w

Pin description of 8086-microprocessor,  Pin Description of 8086 The ...

 Pin Description of 8086 The microprocessor 8086 is a 16-bit CPU available in 3 clock rates, for example 5, 8 and 10 MHz, packaged in a40 pin CERDIP or plastic package. The 8

Multiplication, how we can multiply two 8 bit number with rotation

how we can multiply two 8 bit number with rotation

Find out the content of program, a- Trace the following program fragment an...

a- Trace the following program fragment and find out the content of ax after the          the execution of the program.         X db   5,7  -3,-9,4,-7,9               Mov

Program which allows the user to select from menu, Write a 32-bit program w...

Write a 32-bit program which when run, allows the user to select from a menu: (1)    Enter a Binary Number (2)    Enter a Decimal Number (3)    Enter a Hexadecimal Number

Dma controller-microprocessor, DMA controller :     Steps in...

DMA controller :     Steps include in transferring a block of data from I/O devices (for example a disk) to memory: 1. CPU sends a signal to initiate disk transfe

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