interrupt is a signal send by external device to the processor so as to request the processor to perform a particular work.

A signal informing a program that an events has occurred. when a program receives an interrupt signal, it takes a specified action (which can be to ignore the signal).

Cache momory is a small high-speed memory. it is used for temporary storage of data & information between the main memory and the CPU(center processing unit). The cache memory is only in RAM.

Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. AS the microprocessor processes data, it looks in the cache memory and if it finds the data there.

Cache Memory is scratch pad of computer.

RAM: Read / Write memory, High Speed, Volatile Memory.

ROM: Read only memory, low speed, non volite memory.

Flag is a flip-flop used to store the information about the status of a processor and the status of the insturction executed most recently.

A software or hardware mark that signals a particular condition or status. A flag is like a switch that can be either on or off. The flag said to be set when it is turned on.

stack is portion of RAM used for saving the content of Program Counter and general purpose registers.

LIFO stacks, also known as "push down" stacks, are the conceptually simplest way of saving information in a temporary storage location for such common computer operations as mathematical expression evaluation and recursive subroutine calling.

For D latch: always@(enable) q<=d;

For D flip flop: always@(opsedge clock) q<=d; 

A blocking assignment is one in which the statements are executed sequentially, i.e., first statement is executed and variable is assigned  a value then second is executed and so on. A non blocking assignment is  one in which statements occurs conturrently, only non blocking assignments should be used in sequential circuit.

e.g.

initial

begin

a=b; //blocking

c<=a; //nonblocking

d=c; // blocking

end

In this example firstly the value of b is assigned to a and this value is assigned to c only after execution of first statement. the second and the third statements are executed simultaneously, i.e. value a ais assigned to c and previous value if c is assigned to d.