TRANSLATING A MICROPROGRAM TO HARDWIRE CONTROL

Control unit is the most important portion of CPU The control unit design must include logic for sequencing through micro-ope rations, for executing micro-operations, for interpreting opcodes and making decisions based on ALU flags. The implementation of control unit has been used with a wide variety of techniques such as; Hardwired implementation and Microprogrammed implementation. In hardwired control, it is very time consuming and hard to design. The use of microprogramming simplifies the design of the control unit. but it will be slower in speed than a hardwired unit. Hardwired control is difficult to change or extend the design if it wishes to debug or add a new machine instruction. So this paper will rind an easy way to design by microprogram and to be translated it to Hardwired one on later. To translate the microprogram into actual hardware, it is needed to specify how each field translates into control signals. A microprogram can be implemented with finite state control or a microcode implementation with an explicit sequencer. The finite state machines are usually represented graphically. In this paper, Verilog software is used to translate microprogram to hardware.