8086 Microprocessor is divided into two functional units, i.e., EU (Execution Unit) and BIU (Bus Interface Unit). ... Execution unit gives instructions to BIU stating from where to fetch the data and then decode and execute those instructions.
There was a some register in this microprocessor.There are 4 main register there are AX,BX,CX,DX accumulator register,Base register,Data register,Counter register.There are some special register in this microprocessor there are intruction system, buses and flag registers.