Question

What is ALU and CU within the CPU?

What is a Middleware?

What are the functions of MAR, MDR, IR, PC registers

Answer 1

What is ALU and CU within the CPU?

ALU (Arithmetic Logic Unit):

it is a digital circuit which is used to perform arithmetic and logical opertions such as
arithmetic operations:

addition
substraction
multiplication
division

logical operations:

logical AND
logical OR
logical NOT

it is the basic building block of the CPU.

CU (Control Unit):

it helps in the decode of the instructions such as the instructions might be data transfers or perform oprations on given operands etc..,
it plays a major role in the proper working of all the internal components of CPU.

What is a Middleware?

Middleware:

it is a software bridge which lies between an OS and applications running on it, which enables communication and data management.
in simple terms it is software program which converts one type of data other type of data which can be understood by target application or system.

some middlewares are:
GlassFish
Tomcat
JBoss etc..,

What are the functions of MAR, MDR, IR, PC registers

MAR(Memory Address Register):
it is to handle data transfers between RAM and processor.
it contain the address of main memory to which or from which data to be transferred.

MDR(Memory Data Register):
it is to handle data transfers between RAM and processor.
it contain the data to be read or data to written in the specified address of main memory.

IR(Instruction Register):
It contains the instruction that is currently being executed.
it is usally accessed by control unit to execute the instructions.

PC (Program Counter):
it cntains the address the current instruction being excuted once it has been executed it's been updated with address of the next instruction to be excuted, in this way it executes all the instructions.
it plays a major role in program sucussesful execution.