Electronics

2.Explain the operating modes of 8255 peripheral interface ?

Answer: One

Two

Three vvi

1.Draw the internal architecture of 8086 microprocessor.

Data Registers -
AX = Accumulator Register
BX = Base Register
CX = Count Register
DX = Data Register
Pointer Registers -
SP = Stack Pointer
BP = Base Pointer
IP = Instruction Pointer
ALU = Arithmetic and Logic Unit EU = Execution Unit BIU = Bus Interface Unit

  Instruction Queue
Index Registers -

SI = Source Index
DI = Destination Index
Segment Registers -
CS = Code Segment
DS = Data Segment
SS = Stack Segment
ES = Extra Segment


Transistor: Transistor consists of three layer either two p-types and one n-type or two n-type one p-type. Two p-type and one n-type transistors is known as PNP transistor and two n-type one p-type transistors is known as NPN transistors. Transistor has three terminal emitter, collector and base.

Figure: Transistor

Transistor configurations: 1.Common-base. 2. Common-emitter.  3. Common-collector.

Transistor has three modes: 1. Active mode for amplifier operation. 2. Saturation mode for switch operation. 3. Cutt-off mode for switch operation.

Transistor two types:  1. BJT 2. FET

BJT: A bipolar junction transistor is a bipolar device in which the current flow between two terminals (the collector and the emitter) is controlled by the amount of current that flows through a third terminal (the base). Input is low and output is lower than input.

FET: The field-effect transistor is uni-polar device that uses an electric field to control the shape and hence the conductivity of a channel of one type of charge carrier in a semiconductor material.Input is high output is higher then input.

Semiconductor: The combination of p-type and n-type material is called p-n junction and it is known as semiconductor.