Instruction Pointer:-
•      It is 16-bit register, which identifies the location of the next word of instruction code that is to be fetched in the current code segment.
•      IP contains an offset instead of the actual address of the next instruction.
•      The 20-bit address produced after addition of the offset stored in IP to segment base address in the CS is called the Physical address of the code byte.



The Queue:-
•      The last section of BIU is the FIFO group of registers called a queue. It is basically a group of registers.
•      This arrangement makes possible for the BIU to fetch the instruction byte while EU is decoding an instruction or executing an instruction which does not require use of buses.
•      This arrangement is called pipelining.
•      This is done to speed up the program execution.

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