Registers are assumed to be the basic components of the digital system.
Examples of register operations are shift, count, clear. 2 REGIS TER TRANSFER LEVEL (RTL) NOTATION Themodules of a digital system are bestdefined by a set of registersand theoperations that are performed on the binary information stored in them. we will introduce a design methodology for describing and designing large, complex digital systems. The various mod ules are interco nnected with datapaths and control signals to fonn a d igital sys tem. multiplexers, arith-me tic elements, and control logic. The modules are co nstructe d fro m such dig ita l devices as registers. The sys tem is part itioned into modul ar subsys tems.
To overcome this difficulty, digital systems are designed via a modular approach. To specify a large digital system with a state table is very difficult, because the number of states would be enormous. Sequ ential circuits can bespecified by means of state tables as shown in Chapter 5. A digital system is a seq uential logic system co nstruc ted with flip-flops and gates.
