Describe the function of AX, CX and IP register of 8086 microprocessor .

AX: This is accumulator register. It gets used in arithmetic, logic and data transfer instructions. In manipulation and division, one of the numbers involved must be in AX or AL.

(i) Generates shortest machine code

(ii) Arithmetic, logic and data transfer

(iii) One number must be in AL or AX

(iv) Multiplication & Division

(v) Input & Output

BX: This is base register. BX register is an address register. It usually contain a data pointer used for based, based indexed or register indirect addressing the base address register (divided into BH / BL).

IP (Instruction Painter): To access instructions the 8086 uses the registers CS and IP. The CS register contains the segment number of the next instruction and the IP contains the offset IP is updated each time an instruction is executed so that it will point to the next instruction. Unlike other registers the IP can’t be directly manipulated by an instruction, that is, an instruction may not contain IP as its operand.

(i) Always points to next instruction to be executed

(ii) Offset address relative to CS

IP: Register always works together with CS segment register and it points to currently executing instruction.