By: V. Sai Akhilesh
RNo:180330057

In 8086 Processor The pins and Signals are
Divided Into 5 Categories:
1.Address/data Bus
2.Address/Status Bus
3.Control and Status Signals
4.Interruptes and Externally Initiated Signal
5.Power Supply and Clock frequency Signals


1.Address/Data Bus[AD0-AD15 Pins 16 to2
,39]:. In First clock cycle ,during ALE they
Contain Address Information (A0 to A15) & in
Remaining cycles they contain data(D0 to

D15)
2.Address/Status Bus[A16/S3-A19:Pins 38-
35]:
. In First clock cycle ,during ALE they Contain
Address Information (A16 to A19) & in
Remaining cycles they contain status information(S3-S6)



3.Control & Status Signals
=>RD:Read[output]:pin 32
A low on this signal indicates read operation from memory or I/O
=>BHE/S7 (Bus High Enable/ S7 output): pin34
.It is a low Signal . when low it enables the Msb databus (D8-D15) during read/write operation.

=>NMI : Non mask able interrupt : Pin 17
This is a non mask able Interrupt request to cpu from external devices
=>INTR: Interrupt(Input):Pin 18
It can be enabled or disabled using interrupt flag
=>RESET : Reset(Input):Pin 21
This is a Input signal which resets the
Microprocessor
=>READY : Ready (Input):Pin22
This signal indicates to the CPU whether memory or I/O device is ready For Data Transfer


=> TEST : test (input): Pin23
This Input Signal is used to Synchronize external hardware.
=>MN/MX : Minimum/Maximum : Pin 33
This Signals Selects The Minimum or Maximum mode of operation of the Microprocessor. If low then it is in maximum mode ,if high it works in minimum mode


1.) GND: Ground (input) :Pin 1&20

This Input should be connected to the negative terminal of the DC power supply

2.) CLK: clock(input):pin 19
This input clock signal provides the basic timing for the microprocessor with 33% Duty cycle
=>3.)Vcc :power Supply (input) : Pin 40
This input is connected to the positive terminal of +5V DC power supply


There are 8 signals in these configuration
1.ALE(Address Latch Enable):pin 25
This is used to latch the address & BHE signal
2.DEN(DATA ENABLE): pin26
It is used to activate Data Transceivers
3.DT/R(Data Transmit/Receive):pin 27
It is used to control direction of data bus on data transceivers
4.M/IO(Memory /Input-Output ):pin 28
This signal Selects memory or I/O Operation

5.WR(Write):pin 30
6.INTA(Interrupt Acknowledge):pin 24
7.HLDA(Hold Acknowledge) :pin 30
8.HOLD: Hold

1.Qs1,QS0: Queue Status : pin 24&25
2.S0,S1,S2:Status bits : pin 26,27,28
3.LOCK :pin 29
4.RQ1/GT1,RQ0/GT0: Request/Grant : pin
30,31